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v2.1

Documentation:v2.1

Supported Versions:

CREATE TABLE

Function

CREATE TABLE is used to create an initially empty table in the current database. The table will be owned by the creator.

Precautions

  • For details about the data types supported by column-store tables, see Data Types Supported by Column-store Tables.
  • Column-store tables do not support the array.
  • Column-store tables do not support column generation.
  • Column-store tables cannot be created as global temporary tables.
  • It is recommended that the number of column-store tables do not exceed 1000.
  • If an error occurs during table creation, after it is fixed, the system may fail to delete the empty disk files created before the last automatic clearance. This problem seldom occurs and does not affect system running of the database.
  • Only PARTIAL CLUSTER KEY, UNIQUE, and PRIAMRY KEY can be used as the table-level constraint of column-store tables. Table-level primary key and foreign key constraints are not supported.
  • Only the NULL, NOT NULL, DEFAULT constant values, UNIQUE and PRIMARY KEY can be used as column-store table constraints.
  • Whether column-store tables support a delta table is specified by the enable_delta_store parameter. The threshold for storing data into a delta table is specified by the deltarow_threshold parameter.
  • When JDBC is used, the DEFAULT value can be set through PrepareStatement.
  • The maximum number of columns on each table is 1600, which depends on the column type. The total size of all columns cannot exceed 8192 bytes, except for the columns of variable data types, such as text, varchar, and char.

Syntax

Create a table.

CreateTable ::= CREATE [ [ GLOBAL | LOCAL ] { TEMPORARY | TEMP } | UNLOGGED ] TABLE [ IF NOT EXISTS ] table_name
    ({ column_name data_type [ compress_mode ] [ COLLATE collation ] [ column_constraint [ ... ] ]
        | table_constraint
        | LIKE source_table [ like_option [...] ] }
        [, ... ])
    [ WITH ( {storage_parameter = value} [, ... ] ) ]
    [ ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP } ]
    [ COMPRESS | NOCOMPRESS ]
    [ TABLESPACE tablespace_name ];
  • column_constraint is as follows:

    column_constraint ::= [ CONSTRAINT constraint_name ]
    { NOT NULL |
      NULL |
      CHECK ( expression ) |
      DEFAULT default_expr |
      UNIQUE index_parameters |
      PRIMARY KEY index_parameters |
      REFERENCES reftable [ ( refcolumn ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ]
          [ ON DELETE action ] [ ON UPDATE action ] }
    [ DEFERRABLE | NOT DEFERRABLE | INITIALLY DEFERRED | INITIALLY IMMEDIATE ]
  • compress_mode is as follows:

    compress_mode ::= { DELTA | PREFIX | DICTIONARY | NUMSTR | NOCOMPRESS }
  • table_constraint is as follows:

     table_constraint ::= [ CONSTRAINT constraint_name ]
      { CHECK ( expression ) |
        UNIQUE ( column_name [, ... ] ) index_parameters |
        PRIMARY KEY ( column_name [, ... ] ) index_parameters |
        FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ]
            [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE action ] [ ON UPDATE action ] |
        PARTIAL CLUSTER KEY ( column_name [, ... ] ) }
      [ DEFERRABLE | NOT DEFERRABLE | INITIALLY DEFERRED | INITIALLY IMMEDIATE ]
  • like_option is as follows:

    like_option ::= { INCLUDING | EXCLUDING } { DEFAULTS | GENERATED | CONSTRAINTS | INDEXES | STORAGE | COMMENTS | PARTITION | RELOPTIONS | ALL }
  • index_parameters is as follows:

    index_parameters ::= [ WITH ( {storage_parameter = value} [, ... ] ) ]
    [ USING INDEX TABLESPACE tablespace_name ]

Parameter Description

  • UNLOGGED

    If this keyword is specified, the created table is an unlogged table. Data written to unlogged tables is not written to the WALs, which makes them considerably faster than ordinary tables. However, an unlogged table is automatically truncated after a crash or unclean shutdown, incurring data loss risks. Contents of an unlogged table are also not replicated to standby servers. Any indexes created on an unlogged table are not automatically logged as well.

    Usage scenario: Unlogged tables do not ensure data security. Users can back up data before using unlogged tables; for example, users should back up the data before a system upgrade.

    Troubleshooting: If data is missing in the indexes of unlogged tables due to some unexpected operations such as an unclean shutdown, users should re-create the indexes with errors.

  • GLOBAL | LOCAL

    When creating a temporary table, you can specify the GLOBAL or LOCAL keyword before TEMP or TEMPORARY. If the keyword GLOBAL is specified, MogDB creates a global temporary table. Otherwise, MogDB creates a local temporary table.

  • TEMPORARY | TEMP

    If TEMP or TEMPORARY is specified, the created table is a temporary table. Temporary tables are classified into global temporary tables and local temporary tables. If the keyword GLOBAL is specified when a temporary table is created, the table is a global temporary table. Otherwise, the table is a local temporary table.

    The metadata of the global temporary table is visible to all sessions. After the sessions end, the metadata still exists. The user data, indexes, and statistics of a session are isolated from those of another session. Each session can only view and modify the data submitted by itself. Global temporary tables have two schemas: ON COMMIT PRESERVE ROWS and ON COMMIT PRESERVE ROWS. In session-based ON COMMIT PRESERVE ROWS schema, user data is automatically cleared when a session ends. In transaction-based ON COMMIT DELETE ROWS schema, user data is automatically cleared when the commit or rollback operation is performed. If the ON COMMIT option is not specified during table creation, the session level is used by default. Different from local temporary tables, you can specify a schema that does not start with pg_temp_ when creating a global temporary table.

    A local temporary table is automatically dropped at the end of the current session. Therefore, you can create and use temporary tables in the current session as long as the connected database node in the session is normal. Temporary tables are created only in the current session. If a DDL statement involves operations on temporary tables, a DDL error will be generated. Therefore, you are not advised to perform operations on temporary tables in DDL statements. TEMP is equivalent to TEMPORARY.

    img NOTICE:

    • Local temporary tables are visible to the current session through the schema starting with pg_temp start. Users should not delete schema started with pg_temp or pg_toast_temp.
    • If TEMPORARY or TEMP is not specified when you create a table but its schema is set to that starting with pg_temp_ in the current session, the table will be created as a temporary table.
    • If global temporary tables and indexes are being used by other sessions, do not perform ALTER or DROP.
    • The DDL of a global temporary table affects only the user data and indexes of the current session. For example, TRUNCATE, REINDEX, and ANALYZE are valid only for the current session.
    • You can set the GUC parameter max_active_global_temporary_table to determine whether to enable the global temporary table function. If max_active_global_temporary_table is set to 0, the global temporary table function is disabled.
    • A temporary table is visible only to the current session. Therefore, it cannot be used together with \parallel on.
    • \parallel on: The temporary table does not support primary/standby switchover.
  • IF NOT EXISTS

    Sends a notice, but does not throw an error, if a table with the same name exists.

  • table_name

    Specifies the name of the table to be created.

  • column_name

    Specifies the name of a column to be created in the new table.

  • data_type

    Specifies the data type of the column.

  • compress_mode

    Specifies the compression option of the table. The option specifies the algorithm preferentially used by table columns.

    Value range: DELTA, PREFIX, DICTIONARY, NUMSTR, and NOCOMPRESS

  • COLLATE collation

    Assigns a collation to the column (which must be of a collatable data type). If no collation is specified, the default collation is used. You can run the select * from pg_collation; command to query collation rules from the pg_collation system catalog. The default collation rule is the row starting with default in the query result.

  • LIKE source_table [ like_option … ]

    Specifies a table from which the new table automatically copies all column names, their data types, and their not-null constraints.

    The new table and the original table are decoupled after creation is complete. Changes to the original table will not be applied to the new table, and it is not possible to include data of the new table in scans of the original table.

    Columns and constraints copied by LIKE are not merged with the same name. If the same name is specified explicitly or in another LIKE clause, an error is reported.

    • The default expressions are copied from the original table to the new table only if INCLUDING DEFAULTS is specified. The default behavior is to exclude default expressions, resulting in the copied columns in the new table having default values null.

    • The CHECK constraints are copied from the original table to the new table only when INCLUDING CONSTRAINTS is specified. Other types of constraints are never copied to the new table. Not-null constraints are always copied to the new table. These rules also apply to column constraints and table constraints.

    • Any indexes on the original table will not be created on the new table, unless the INCLUDING INDEXES clause is specified.

    • STORAGE settings for the copied column definitions are copied only if INCLUDING STORAGE is specified. The default behavior is to exclude STORAGE settings.

    • If INCLUDING COMMENTS is specified, comments for the copied columns, constraints, and indexes are copied. The default behavior is to exclude comments.

    • If INCLUDING PARTITION is specified, the partition definitions of the source table are copied to the new table, and the new table no longer uses the PARTITION BY clause. The default behavior is to exclude partition definition of the original table. If the source table has an index, you can use the INCLUDING PARTITION INCLUDING INDEXES syntax. If only INCLUDING INDEXES is used for a partitioned table, the target table will be defined as an ordinary table, but the index is a partitioned index. In this case, an error will be reported because ordinary tables do not support partitioned indexes.

    • If INCLUDING RELOPTIONS is specified, the new table will copy the storage parameter (that is, WITH clause) of the source table. The default behavior is to exclude partition definition of the storage parameter of the original table.

    • INCLUDING ALL contains the meaning of INCLUDING DEFAULTS, INCLUDING CONSTRAINTS, INCLUDING INDEXES, INCLUDING STORAGE, INCLUDING COMMENTS, INCLUDING PARTITION, and INCLUDING RELOPTIONS.

      img NOTICE:

      • If the source table contains a sequence with the SERIAL, BIGSERIAL, or SMALLSERIAL data type, or a column in the source table is a sequence by default and the sequence is created for this table by using CREATE SEQUENCE… OWNED BY, these sequences will not be copied to the new table, and another sequence specific to the new table will be created. This is different from earlier versions. To share a sequence between the source table and new table, create a shared sequence (do not use OWNED BY) and set a column in the source table to this sequence.
      • You are not advised to set a column in the source table to the sequence specific to another table especially when the table is distributed in specific node groups, because doing so may result in CREATE TABLE … LIKE execution failures. In addition, doing so may cause the sequence to become invalid in the source sequence because the sequence will also be deleted from the source table when it is deleted from the table that the sequence is specific to. To share a sequence among multiple tables, you are advised to create a shared sequence for them.
      • EXCLUDING of a partitioned table must be used together with INCLUDING ALL, for example, INCLUDING ALL EXCLUDING DEFAULTS, except for DEFAULTS of the source partitioned table.
  • WITH ( { storage_parameter = value } [, … ] )

    Specifies an optional storage parameter for a table or an index.

    img NOTE: When using Numeric of any precision to define a column, specifies precision p and scale s. When precision and scale are not specified, the input will be displayed.

    The description of parameters is as follows:

    • FILLFACTOR

      The fill factor of a table is a percentage from 10 to 100. 100 (complete filling) is the default value. When a smaller fill factor is specified, INSERT operations pack table pages only to the indicated percentage. The remaining space on each page is reserved for updating rows on that page. This gives UPDATE a chance to place the updated copy of a row on the same page, which is more efficient than placing it on a different page. For a table whose entries are never updated, setting the fill factor to 100 (complete filling) is the best choice, but in heavily updated tables a smaller fill factor would be appropriate. The parameter has no meaning for column-store tables.

      Value range: 10-100

    • ORIENTATION

      Specifies the storage mode (row-store, column-store, or ORC) of table data. This parameter cannot be modified once it is set.

      Value range:

      • ROW indicates that table data is stored in rows.

        ROW applies to OLTP service and scenarios with a large number of point queries or addition/deletion operations.

      • COLUMN indicates that the data is stored in columns.

        COLUMN applies to the data warehouse service, which has a large amount of aggregation computing, and involves a few column operations.

        Default value:

        If an ordinary tablespace is specified, the default is ROW.

    • STORAGE_TYPE

      Specifies the storage engine type. This parameter cannot be modified once it is set.

      Value range:

      • USTORE indicates that tables support the Inplace-Update storage engine.
      • ASTORE indicates that tables support the Append-Only storage engine.

      Default value:

      If no table is specified, data is stored in Append-Only mode by default.

    • COMPRESSION

      Specifies the compression level of table data. It determines the compression ratio and time. Generally, the higher the level of compression, the higher the ratio, the longer the time; and the lower the level of compression, the lower the ratio, the shorter the time. The actual compression ratio depends on the distribution mode of table data loaded. MogDB supports compression of row-store tables since version 2.1.

      Value range:

      The valid values for column-store tables are YES, NO, LOW, MIDDLE, and HIGH, and the default value is LOW.

    • COMPRESSLEVEL

      Specifies the table data compression ratio and duration at the same compression level. This divides a compression level into sublevels, providing more choices for compression ratio and duration. As the value becomes greater, the compression ratio becomes higher and duration longer at the same compression level.

      Value range: 0 to 3. The default value is 0.

    • MAX_BATCHROW

      Specifies the maximum number of rows in a storage unit during data loading. The parameter is only valid for column-store tables.

      Value range: 10000 to 60000. The default value is 60000.

    • PARTIAL_CLUSTER_ROWS

      Specifies the number of records to be partially clustered for storage during data loading. The parameter is only valid for column-store tables.

      Value range: greater than or equal to MAX_BATCHROW. You are advised to set this parameter to an integer multiple of MAX_BATCHROW.

    • DELTAROW_THRESHOLD

      Specifies the upper limit of to-be-imported rows for triggering the data import to a delta table when data of a column-store table is to be imported. This parameter takes effect only if enable_delta_store is set to on. The parameter is only valid for column-store tables.

      Value range: from 0 to 9999. The default value is 100.

    • VERSION

      Specifies the version of ORC storage format.

      Value range: 0.12. ORC 0.12 format is supported currently. More formats will be supported as the development of ORC format.

      Default value: 0.12

    • segment

      The data is stored in segment-page mode. This parameter supports only row-store tables. Column-store tables, temporary tables, and unlogged tables are not supported. The ustore storage engine is not supported.

      Value range: on and off

      Default value: off

    • dek_cipher

      Ciphertext of the key used for transparent data encryption. When enable_tde is enabled, the system automatically applies for ciphertext creation. You cannot specify the ciphertext. The key rotation function can be used to update the key.

      Value range: a string.

      If encryption is disabled, the default value is null by default.

  • ON COMMIT { PRESERVE ROWS | DELETE ROWS | DROP }

    ON COMMIT determines what to do when you commit a temporary table creation operation. The three options are as follows. Currently, only PRESERVE ROWS and DELETE ROWS can be used.

    • PRESERVE ROWS (default): No special action is taken at the ends of transactions. The temporary table and its table data are unchanged.
    • DELETE ROWS: All rows in the temporary table will be deleted at the end of each transaction block.
    • DROP: The temporary table will be dropped at the end of the current transaction block. Only local temporary tables can be dropped. Global temporary tables cannot be dropped.
  • COMPRESS | NOCOMPRESS

    If you specify COMPRESS in the CREATE TABLE statement, the compression feature is triggered in case of a bulk INSERT operation. If this feature is enabled, a scan is performed for all tuple data within the page to generate a dictionary and then the tuple data is compressed and stored. If NOCOMPRESS is specified, the table is not compressed.

    Default value: NOCOMPRESS, that is, tuple data is not compressed before storage.

  • TABLESPACE tablespace_name

    Specifies the tablespace where the new table is created. If not specified, the default tablespace is used.

  • CONSTRAINT constraint_name

    Specifies the name of a column or table constraint. The optional constraint clauses specify constraints that new or updated rows must satisfy for an insert or update operation to succeed.

    There are two ways to define constraints:

    • A column constraint is defined as part of a column definition, and it is bound to a particular column.
    • A table constraint is not bound to a particular column but can apply to more than one column.
  • NOT NULL

    The column is not allowed to contain null values.

  • NULL

    The column is allowed to contain null values. This is the default setting.

    This clause is only provided for compatibility with non-standard SQL databases. It is not recommended.

  • CHECK ( expression )

    Specifies an expression producing a Boolean result where the insert or update operation of new or updated rows can succeed only when the expression result is TRUE or UNKNOWN; otherwise, an error is thrown and the database is not altered.

    A check constraint specified as a column constraint should reference only the column's values, while an expression appearing in a table constraint can reference multiple columns.

    img NOTE: <>NULL and !=NULL are invalid in an expression. Change them to IS NOT NULL.

  • DEFAULT default_expr

    Assigns a default data value for a column. The value can be any variable-free expressions. (Subqueries and cross-references to other columns in the current table are not allowed.) The data type of the default expression must match the data type of the column.

    The default expression will be used in any insert operation that does not specify a value for the column. If there is no default value for a column, then the default value is null.

  • UNIQUE index_parameters

    UNIQUE ( column_name [, … ] ) index_parameters

    Specifies that a group of one or more columns of a table can contain only unique values.

    For the purpose of a unique constraint, null is not considered equal.

  • PRIMARY KEY index_parameters

    PRIMARY KEY ( column_name [, … ] ) index_parameters

    Specifies that a column or columns of a table can contain only unique (non-duplicate) and non-null values.

    Only one primary key can be specified for a table.

  • DEFERRABLE | NOT DEFERRABLE

    They determine whether the constraint is deferrable. A constraint that is not deferrable will be checked immediately after every command. Checking of constraints that are deferrable can be postponed until the end of the transaction using the SET CONSTRAINTS command. NOT DEFERRABLE is the default value. Currently, only UNIQUE constraints, primary key constraints, and foreign key constraints accept this clause. All the other constraints are not deferrable.

  • PARTIAL CLUSTER KEY

    Specifies a partial cluster key for storage. When importing data to a column-store table, you can perform local data sorting by specified columns (single or multiple).

  • INITIALLY IMMEDIATE | INITIALLY DEFERRED

    If a constraint is deferrable, this clause specifies the default time to check the constraint.

    • If the constraint is INITIALLY IMMEDIATE (default value), it is checked after each statement.

    • If the constraint is INITIALLY DEFERRED, it is checked only at the end of the transaction.

      The constraint check time can be altered using the SET CONSTRAINTS statement.

  • USING INDEX TABLESPACE tablespace_name

    Allows selection of the tablespace in which the index associated with a UNIQUE or PRIMARY KEY constraint will be created. If not specified, default_tablespace is consulted, or the default tablespace in the database if default_tablespace is empty.

  • ENCRYPTION_TYPE = encryption_type_value

    For the encryption type in the ENCRYPTED WITH constraint, the value of encryption_type_value is DETERMINISTIC or RANDOMIZED.

Example

-- Create a simple table.
mogdb=# CREATE TABLE tpcds.warehouse_t1
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

mogdb=# CREATE TABLE tpcds.warehouse_t2
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)         DICTIONARY,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);
-- Create a table and set the default value of the W_STATE column to GA.
mogdb=# CREATE TABLE tpcds.warehouse_t3
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)           DEFAULT 'GA',
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

-- Create a table and check whether the W_WAREHOUSE_NAME column is unique at the end of its creation.
mogdb=# CREATE TABLE tpcds.warehouse_t4
(
    W_WAREHOUSE_SK            INTEGER                NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)               NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)   UNIQUE DEFERRABLE,
    W_WAREHOUSE_SQ_FT         INTEGER                        ,
    W_STREET_NUMBER           CHAR(10)                       ,
    W_STREET_NAME             VARCHAR(60)                    ,
    W_STREET_TYPE             CHAR(15)                       ,
    W_SUITE_NUMBER            CHAR(10)                       ,
    W_CITY                    VARCHAR(60)                    ,
    W_COUNTY                  VARCHAR(30)                    ,
    W_STATE                   CHAR(2)                        ,
    W_ZIP                     CHAR(10)                       ,
    W_COUNTRY                 VARCHAR(20)                    ,
    W_GMT_OFFSET              DECIMAL(5,2)
);
-- Create a table with its fill factor set to 70%.
mogdb=# CREATE TABLE tpcds.warehouse_t5
(
    W_WAREHOUSE_SK            INTEGER                NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)               NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                    ,
    W_WAREHOUSE_SQ_FT         INTEGER                        ,
    W_STREET_NUMBER           CHAR(10)                       ,
    W_STREET_NAME             VARCHAR(60)                    ,
    W_STREET_TYPE             CHAR(15)                       ,
    W_SUITE_NUMBER            CHAR(10)                       ,
    W_CITY                    VARCHAR(60)                    ,
    W_COUNTY                  VARCHAR(30)                    ,
    W_STATE                   CHAR(2)                        ,
    W_ZIP                     CHAR(10)                       ,
    W_COUNTRY                 VARCHAR(20)                    ,
    W_GMT_OFFSET              DECIMAL(5,2),
    UNIQUE(W_WAREHOUSE_NAME) WITH(fillfactor=70)
);

-- Alternatively, user the following syntax:
mogdb=# CREATE TABLE tpcds.warehouse_t6
(
    W_WAREHOUSE_SK            INTEGER                NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)               NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)              UNIQUE,
    W_WAREHOUSE_SQ_FT         INTEGER                        ,
    W_STREET_NUMBER           CHAR(10)                       ,
    W_STREET_NAME             VARCHAR(60)                    ,
    W_STREET_TYPE             CHAR(15)                       ,
    W_SUITE_NUMBER            CHAR(10)                       ,
    W_CITY                    VARCHAR(60)                    ,
    W_COUNTY                  VARCHAR(30)                    ,
    W_STATE                   CHAR(2)                        ,
    W_ZIP                     CHAR(10)                       ,
    W_COUNTRY                 VARCHAR(20)                    ,
    W_GMT_OFFSET              DECIMAL(5,2)
) WITH(fillfactor=70);

-- Create a table and specify that its data is not written to WALs.
mogdb=# CREATE UNLOGGED TABLE tpcds.warehouse_t7
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

-- Create a temporary table.
mogdb=# CREATE TEMPORARY TABLE warehouse_t24
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

-- Create a local temporary table and specify that this table is dropped when the transaction is committed.
mogdb=# CREATE TEMPORARY TABLE warehouse_t25
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
) ON COMMIT DELETE ROWS;

-- Create a global temporary table and specify that this table data is deleted when the session ends.
mogdb=# CREATE GLOBAL TEMPORARY TABLE gtt1
(
    ID                        INTEGER               NOT NULL,
    NAME                      CHAR(16)              NOT NULL,
    ADDRESS                   VARCHAR(50)                   ,
    POSTCODE                  CHAR(6)
) ON COMMIT PRESERVE ROWS;

-- Create a table and specify that no error is reported for duplicate tables (if any).
mogdb=# CREATE TABLE IF NOT EXISTS tpcds.warehouse_t8
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

-- Create a general tablespace.
mogdb=# CREATE TABLESPACE DS_TABLESPACE1 RELATIVE LOCATION 'tablespace/tablespace_1';
-- Specify a tablespace when creating a table.
mogdb=# CREATE TABLE tpcds.warehouse_t9
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
) TABLESPACE DS_TABLESPACE1;

-- Separately specify the index tablespace for W_WAREHOUSE_NAME when creating the table.
mogdb=# CREATE TABLE tpcds.warehouse_t10
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)           UNIQUE USING INDEX TABLESPACE DS_TABLESPACE1,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);
-- Create a table with a primary key constraint.
mogdb=# CREATE TABLE tpcds.warehouse_t11
(
    W_WAREHOUSE_SK            INTEGER            PRIMARY KEY,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

-- An alternative for the preceding syntax is as follows:
mogdb=# CREATE TABLE tpcds.warehouse_t12
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2),
    PRIMARY KEY(W_WAREHOUSE_SK)
);

-- Or use the following statement to specify the name of the constraint:
mogdb=# CREATE TABLE tpcds.warehouse_t13
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2),
    CONSTRAINT W_CSTR_KEY1 PRIMARY KEY(W_WAREHOUSE_SK)
);

-- Create a table with a compound primary key constraint.
mogdb=# CREATE TABLE tpcds.warehouse_t14
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2),
    CONSTRAINT W_CSTR_KEY2 PRIMARY KEY(W_WAREHOUSE_SK, W_WAREHOUSE_ID)
);

-- Create a column-store table.
mogdb=# CREATE TABLE tpcds.warehouse_t15
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
) WITH (ORIENTATION = COLUMN);

-- Create a column-store table using partial clustered storage.
mogdb=# CREATE TABLE tpcds.warehouse_t16
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2),
    PARTIAL CLUSTER KEY(W_WAREHOUSE_SK, W_WAREHOUSE_ID)
) WITH (ORIENTATION = COLUMN);

-- Define a column-store table with compression enabled.
mogdb=# CREATE TABLE tpcds.warehouse_t17
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
) WITH (ORIENTATION = COLUMN, COMPRESSION=HIGH);

-- Define a row-store table with compression enabled.
mogdb=# CREATE TABLE table_3213
(
  c_w_id         integer        not null,
  c_d_id         integer        not null,
  c_id           integer        not null,
  c_discount     decimal(4,4),
  c_credit       char(2),
  c_last         varchar(16),
  c_first        varchar(16),
  c_credit_lim   decimal(12,2),
  c_balance      decimal(12,2),
  c_ytd_payment  decimal(12,2),
  c_payment_cnt  integer,
  c_delivery_cnt integer,
  c_street_1     varchar(20),
  c_street_2     varchar(20),
  c_city         varchar(20),
  c_state        char(2),
  c_zip          char(9),
  c_phone        char(16),
  c_since        timestamp,
  c_middle       char(2),
  c_data         varchar(500)
) WITH (COMPRESSION = YES);

--specify the column mode when creating a row-compressed table.
mogdb=# CREATE TABLE compress_18
(
  a00 int DELTA,
  a01 int DICTIONARY,
  a02 int NOCOMPRESS,
  a03 varchar(100) PREFIX,
  a04 int
) WITH (COMPRESSION = YES);

--For a row-compressed table created by WITH (COMPRESSION = YES), or a row-compressed table modified by SET COMPRESS, the mode of the new column can be specified in the following way.
mogdb=# ALTER TABLE test1 ADD COLUMN al char(5) PREFIX;

-- Define a column check constraint.
mogdb=# CREATE TABLE tpcds.warehouse_t19
(
    W_WAREHOUSE_SK            INTEGER               PRIMARY KEY CHECK (W_WAREHOUSE_SK > 0),
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)           CHECK (W_WAREHOUSE_NAME IS NOT NULL),
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2)
);

mogdb=# CREATE TABLE tpcds.warehouse_t20
(
    W_WAREHOUSE_SK            INTEGER               PRIMARY KEY,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)           CHECK (W_WAREHOUSE_NAME IS NOT NULL),
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2),
    CONSTRAINT W_CONSTR_KEY2 CHECK(W_WAREHOUSE_SK > 0 AND W_WAREHOUSE_NAME IS NOT NULL)
);

-- Define a hash table.
mogdb=# CREATE TABLE tpcds.warehouse_t22
(
    W_WAREHOUSE_SK            INTEGER               NOT NULL,
    W_WAREHOUSE_ID            CHAR(16)              NOT NULL,
    W_WAREHOUSE_NAME          VARCHAR(20)                   ,
    W_WAREHOUSE_SQ_FT         INTEGER                       ,
    W_STREET_NUMBER           CHAR(10)                      ,
    W_STREET_NAME             VARCHAR(60)                   ,
    W_STREET_TYPE             CHAR(15)                      ,
    W_SUITE_NUMBER            CHAR(10)                      ,
    W_CITY                    VARCHAR(60)                   ,
    W_COUNTY                  VARCHAR(30)                   ,
    W_STATE                   CHAR(2)                       ,
    W_ZIP                     CHAR(10)                      ,
    W_COUNTRY                 VARCHAR(20)                   ,
    W_GMT_OFFSET              DECIMAL(5,2),
    CONSTRAINT W_CONSTR_KEY3 UNIQUE(W_WAREHOUSE_SK)
);

-- Add a varchar column to the tpcds.warehouse_t19 table.
mogdb=# ALTER TABLE tpcds.warehouse_t19 ADD W_GOODS_CATEGORY varchar(30);

-- Add a check constraint to the tpcds.warehouse_t19 table.
mogdb=# ALTER TABLE tpcds.warehouse_t19 ADD CONSTRAINT W_CONSTR_KEY4 CHECK (W_STATE IS NOT NULL);

-- Use one statement to alter the types of two existing columns.
mogdb=# ALTER TABLE tpcds.warehouse_t19
    ALTER COLUMN W_GOODS_CATEGORY TYPE varchar(80),
    ALTER COLUMN W_STREET_NAME TYPE varchar(100);

-- This statement is equivalent to the preceding statement.
mogdb=# ALTER TABLE tpcds.warehouse_t19 MODIFY (W_GOODS_CATEGORY varchar(30), W_STREET_NAME varchar(60));

-- Add a not-null constraint to an existing column.
mogdb=# ALTER TABLE tpcds.warehouse_t19 ALTER COLUMN W_GOODS_CATEGORY SET NOT NULL;

-- Drop not-null constraints from an existing column.
mogdb=# ALTER TABLE tpcds.warehouse_t19 ALTER COLUMN W_GOODS_CATEGORY DROP NOT NULL;

-- If no partial cluster is specified in a column-store table, add a partial cluster to the table.
mogdb=# ALTER TABLE tpcds.warehouse_t17 ADD PARTIAL CLUSTER KEY(W_WAREHOUSE_SK);

-- View the constraint name and drop the partial cluster column of a column-store table.
mogdb=# \d+ tpcds.warehouse_t17
                              Table "tpcds.warehouse_t17"
      Column       |         Type          | Modifiers | Storage  | Stats target | Description
-------------------+-----------------------+-----------+----------+--------------+-------------
 w_warehouse_sk    | integer               | not null  | plain    |              |
 w_warehouse_id    | character(16)         | not null  | extended |              |
 w_warehouse_name  | character varying(20) |           | extended |              |
 w_warehouse_sq_ft | integer               |           | plain    |              |
 w_street_number   | character(10)         |           | extended |              |
 w_street_name     | character varying(60) |           | extended |              |
 w_street_type     | character(15)         |           | extended |              |
 w_suite_number    | character(10)         |           | extended |              |
 w_city            | character varying(60) |           | extended |              |
 w_county          | character varying(30) |           | extended |              |
 w_state           | character(2)          |           | extended |              |
 w_zip             | character(10)         |           | extended |              |
 w_country         | character varying(20) |           | extended |              |
 w_gmt_offset      | numeric(5,2)          |           | main     |              |
Partial Cluster :
    "warehouse_t17_cluster" PARTIAL CLUSTER KEY (w_warehouse_sk)
Has OIDs: no
Location Nodes: ALL DATANODES
Options: compression=no, version=0.12
mogdb=# ALTER TABLE tpcds.warehouse_t17 DROP CONSTRAINT warehouse_t17_cluster;

-- Move a table to another tablespace.
mogdb=# ALTER TABLE tpcds.warehouse_t19 SET TABLESPACE PG_DEFAULT;
-- Create the joe schema.
mogdb=# CREATE SCHEMA joe;

-- Move a table to another schema.
mogdb=# ALTER TABLE tpcds.warehouse_t19 SET SCHEMA joe;

-- Rename an existing table.
mogdb=# ALTER TABLE joe.warehouse_t19 RENAME TO warehouse_t23;

-- Drop a column from the warehouse_t23 table.
mogdb=# ALTER TABLE joe.warehouse_t23 DROP COLUMN W_STREET_NAME;

-- Drop the tablespace, schema joe, and schema tables warehouse.
mogdb=# DROP TABLE tpcds.warehouse_t1;
mogdb=# DROP TABLE tpcds.warehouse_t2;
mogdb=# DROP TABLE tpcds.warehouse_t3;
mogdb=# DROP TABLE tpcds.warehouse_t4;
mogdb=# DROP TABLE tpcds.warehouse_t5;
mogdb=# DROP TABLE tpcds.warehouse_t6;
mogdb=# DROP TABLE tpcds.warehouse_t7;
mogdb=# DROP TABLE tpcds.warehouse_t8;
mogdb=# DROP TABLE tpcds.warehouse_t9;
mogdb=# DROP TABLE tpcds.warehouse_t10;
mogdb=# DROP TABLE tpcds.warehouse_t11;
mogdb=# DROP TABLE tpcds.warehouse_t12;
mogdb=# DROP TABLE tpcds.warehouse_t13;
mogdb=# DROP TABLE tpcds.warehouse_t14;
mogdb=# DROP TABLE tpcds.warehouse_t15;
mogdb=# DROP TABLE tpcds.warehouse_t16;
mogdb=# DROP TABLE tpcds.warehouse_t17;
mogdb=# DROP TABLE tpcds.warehouse_t18;
mogdb=# DROP TABLE tpcds.warehouse_t20;
mogdb=# DROP TABLE tpcds.warehouse_t21;
mogdb=# DROP TABLE tpcds.warehouse_t22;
mogdb=# DROP TABLE joe.warehouse_t23;
mogdb=# DROP TABLE tpcds.warehouse_t24;
mogdb=# DROP TABLE tpcds.warehouse_t25;
mogdb=# DROP TABLESPACE DS_TABLESPACE1;
mogdb=# DROP SCHEMA IF EXISTS joe CASCADE;

ALTER TABLE, DROP TABLE, and CREATE TABLESPACE

Suggestions

  • UNLOGGED
    • The unlogged table and its indexes do not use the WAL log mechanism during data writing. Their write speed is much higher than that of ordinary tables. Therefore, they can be used for storing intermediate result sets of complex queries to improve query performance.
    • The unlogged table has no primary/standby mechanism. In case of system faults or abnormal breakpoints, data loss may occur. Therefore, the unlogged table cannot be used to store basic data.
  • TEMPORARY | TEMP
    • A temporary table is automatically dropped at the end of a session.
  • LIKE
    • The new table automatically inherits all column names, data types, and not-null constraints from this table. The new table is irrelevant to the original table after the creation.
  • LIKE INCLUDING DEFAULTS
    • The default expressions are copied from the original table to the new table only if INCLUDING DEFAULTS is specified. The default behavior is to exclude default expressions, resulting in the copied columns in the new table having default values null.
  • LIKE INCLUDING CONSTRAINTS
    • The CHECK constraints are copied from the original table to the new table only when INCLUDING CONSTRAINTS is specified. Other types of constraints are never copied to the new table. Not-null constraints are always copied to the new table. These rules also apply to column constraints and table constraints.
  • LIKE INCLUDING INDEXES
    • Any indexes on the original table will not be created on the new table, unless the INCLUDING INDEXES clause is specified.
  • LIKE INCLUDING STORAGE
    • STORAGE settings for the copied column definitions are copied only if INCLUDING STORAGE is specified. The default behavior is to exclude STORAGE settings.
  • LIKE INCLUDING COMMENTS
    • If INCLUDING COMMENTS is specified, comments for the copied columns, constraints, and indexes are copied. The default behavior is to exclude comments.
  • LIKE INCLUDING PARTITION
    • If INCLUDING PARTITION is specified, the partition definitions of the source table are copied to the new table, and the new table no longer uses the PARTITION BY clause. The default behavior is to exclude partition definition of the original table.
  • LIKE INCLUDING RELOPTIONS
    • If INCLUDING RELOPTIONS is specified, the new table will copy the storage parameter (that is, WITH clause) of the source table. The default behavior is to exclude partition definition of the storage parameter of the original table.
  • LIKE INCLUDING ALL
    • INCLUDING ALL contains the meaning of INCLUDING DEFAULTS, INCLUDING CONSTRAINTS, INCLUDING INDEXES, INCLUDING STORAGE, INCLUDING COMMENTS, INCLUDING PARTITION, and INCLUDING RELOPTIONS.
  • ORIENTATION ROW
    • Creates a row-store table. Row-store applies to the OLTP service, which has many interactive transactions. An interaction involves many columns in the table. Using row-store can improve the efficiency.
  • ORIENTATION COLUMN
    • Creates a column-store table. Column-store applies to the DWS, which has a large amount of aggregation computing, and involves a few column operations.
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