- About MogDB
- Quick Start
- Characteristic Description
- Overview
- High Performance
- CBO Optimizer
- LLVM
- Vectorized Engine
- Hybrid Row-Column Store
- Adaptive Compression
- Adaptive Two-phase Hash Aggregation
- SQL Bypass
- Kunpeng NUMA Architecture Optimization
- High Concurrency of Thread Pools
- SMP for Parallel Execution
- Xlog no Lock Flush
- Parallel Page-based Redo For Ustore
- Row-Store Execution to Vectorized Execution
- Astore Row Level Compression
- BTree Index Compression
- Tracing SQL Function
- Parallel Index Scan
- Parallel Query Optimization
- Enhancement of Tracing Backend Key Thread
- Ordering Operator Optimization
- OCK-accelerated Data Transmission
- OCK SCRLock Accelerate Distributed Lock
- Enhancement of WAL Redo Performance
- Enhancement of Dirty Pages Flushing Performance
- Sequential Scan Prefetch
- Ustore SMP Parallel Scanning
- Statement Level PLSQL Function Cache Support
- High Availability (HA)
- Primary/Standby
- Logical Replication
- Logical Backup
- Physical Backup
- Automatic Job Retry upon Failure
- Ultimate RTO
- High Availability Based on the Paxos Protocol
- Cascaded Standby Server
- Delayed Replay
- Adding or Deleting a Standby Server
- Delaying Entering the Maximum Availability Mode
- Parallel Logical Decoding
- DCF
- CM(Cluster Manager)
- Global SysCache
- Using a Standby Node to Build a Standby Node
- Two City and Three Center DR
- CM Cluster Management Component Supporting Two Node Deployment
- Query of the Original DDL Statement for a View
- MogDB/CM/PTK Dual Network Segment Support
- Enhanced Efficiency of Logical Backup and Restore
- Maintainability
- Workload Diagnosis Report (WDR)
- Slow SQL Diagnosis
- Session Performance Diagnosis
- System KPI-aided Diagnosis
- Fault Diagnosis
- Extension Splitting
- Built-in Stack Tool
- SQL PATCH
- Lightweight Lock Export and Analysis
- DCF Module Tracing
- Error When Writing Illegal Characters
- Support For Pageinspect & Pagehack
- Autonomous Transaction Management View and Termination
- Corrupt Files Handling
- Compatibility
- Add %rowtype Attribute To The View
- Aggregate Functions Distinct Performance Optimization
- Aggregate Functions Support Keep Clause
- Aggregate Functions Support Scenario Extensions
- Compatible With MySQL Alias Support For Single Quotes
- current_date/current_time Keywords As Field Name
- Custom Type Array
- For Update Support Outer Join
- MogDB Supports Insert All
- Oracle DBLink Syntax Compatibility
- Remove Type Conversion Hint When Creating PACKAGE/FUNCTION/PROCEDURE
- Support Bypass Method When Merge Into Hit Index
- Support For Adding Nocopy Attributes To Procedure And Function Parameters
- Support For Passing The Count Attribute Of An Array As A Parameter Of The Array Extend
- Support Q Quote Escape Character
- Support Subtracting Two Date Types To Return Numeric Type
- Support table()
- Support To Keep The Same Name After The End With Oracle
- Support Where Current Of
- Support For Constants In Package As Default Values
- Support PLPGSQL subtype
- Support Synonym Calls Without Parentheses For Function Without Parameters
- Support For dbms_utility.format_error_backtrace
- Support for PIVOT and UNPIVOT Syntax
- Mod Function Compatibility
- Support for Nesting of Aggregate Functions
- ORDER BY/GROUP BY Scenario Expansion
- Support for Modifying Table Log Properties After Table Creation
- Support for INSERT ON CONFLICT Clause
- Support for AUTHID CURRENT_USER
- Support for Stored Procedure OUT Parameters in PBE Mode
- Database Security
- Access Control Model
- Separation of Control and Access Permissions
- Database Encryption Authentication
- Data Encryption and Storage
- Database Audit
- Network Communication Security
- Resource Label
- Unified Audit
- Dynamic Data Anonymization
- Row-Level Access Control
- Password Strength Verification
- Equality Query in a Fully-encrypted Database
- Ledger Database Mechanism
- Transparent Data Encryption
- Enterprise-Level Features
- Support for Functions and Stored Procedures
- SQL Hints
- Full-Text Indexing
- Copy Interface for Error Tolerance
- Partitioning
- Support for Advanced Analysis Functions
- Materialized View
- HyperLogLog
- Creating an Index Online
- Autonomous Transaction
- Global Temporary Table
- Pseudocolumn ROWNUM
- Stored Procedure Debugging
- JDBC Client Load Balancing and Read/Write Isolation
- In-place Update Storage Engine
- Publication-Subscription
- Foreign Key Lock Enhancement
- Data Compression in OLTP Scenarios
- Transaction Async Submit
- Index Creation Parallel Control
- Dynamic Partition Pruning
- COPY Import Optimization
- SQL Running Status Observation
- BRIN Index
- BLOOM Index
- Event Trigger
- Scrollable Cursor Support for Reverse Retrieval
- Support for Pruning Subquery Projection Columns
- Pruning ORDER BY in Subqueries
- Automatic Creation of Indexes Supporting Fuzzy Matching
- Support for Importing and Exporting Specific Objects
- Application Development Interfaces
- AI Capabilities
- Middleware
- Workload Management
- Installation Guide
- Upgrade Guide
- Administrator Guide
- Localization
- Routine Maintenance
- Starting and Stopping MogDB
- Using the gsql Client for Connection
- Routine Maintenance
- Checking OS Parameters
- Checking MogDB Health Status
- Checking Database Performance
- Checking and Deleting Logs
- Checking Time Consistency
- Checking The Number of Application Connections
- Routinely Maintaining Tables
- Routinely Recreating an Index
- Exporting and Viewing the WDR
- Data Security Maintenance Suggestions
- Slow SQL Diagnosis
- Log Reference
- Primary and Standby Management
- Column-store Tables Management
- Backup and Restoration
- Database Deployment Solutions
- Importing and Exporting Data
- High Available Guide
- AI Features Guide
- AI4DB: Autonomous Database O&M
- DBMind Mode
- Components that Support DBMind
- AI Sub-functions of the DBMind
- ABO Optimizer
- DB4AI: Database-driven AI
- AI4DB: Autonomous Database O&M
- Security Guide
- Developer Guide
- Application Development Guide
- Development Specifications
- Development Based on JDBC
- JDBC Package, Driver Class, and Environment Class
- Development Process
- Loading the Driver
- Connecting to a Database
- Connecting to the Database (Using SSL)
- Connecting to the Database (Using UDS)
- Running SQL Statements
- Processing Data in a Result Set
- Closing a Connection
- Managing Logs
- Example: Common Operations
- Example: Retrying SQL Queries for Applications
- Example: Importing and Exporting Data Through Local Files
- Example 2: Migrating Data from a MY Database to MogDB
- Example: Logic Replication Code
- Example: Parameters for Connecting to the Database in Different Scenarios
- Example: JDBC Primary/Standby Cluster Load Balancing
- JDBC API Reference
- java.sql.Connection
- java.sql.CallableStatement
- java.sql.DatabaseMetaData
- java.sql.Driver
- java.sql.PreparedStatement
- java.sql.ResultSet
- java.sql.ResultSetMetaData
- java.sql.Statement
- javax.sql.ConnectionPoolDataSource
- javax.sql.DataSource
- javax.sql.PooledConnection
- javax.naming.Context
- javax.naming.spi.InitialContextFactory
- CopyManager
- JDBC-based Common Parameter Reference
- JDBC Release Notes
- Development Based on ODBC
- Development Based on libpq
- Psycopg2-Based Development
- Commissioning
- Stored Procedure
- User Defined Functions
- PL/pgSQL-SQL Procedural Language
- Scheduled Jobs
- Autonomous Transaction
- Logical Replication
- Extension
- MySQL Compatibility Description
- Dolphin Extension
- Dolphin Overview
- Dolphin Installation
- Dolphin Restrictions
- Dolphin Syntax
- SQL Reference
- Keywords
- Data Types
- Functions and Operators
- Assignment Operators
- Character Processing Functions and Operators
- Arithmetic Functions and Operators
- Dolphin Lock
- Date and Time Processing Functions and Operators
- Advisory Lock Functions
- Network Address Functions and Operators
- Conditional Expression Functions
- Aggregate Functions
- System Information Functions
- Logical Operators
- Bit String Functions and Operators
- JSON-JSONB Functions and Operators
- Type Conversion Functions
- Compatible Operators and Operations
- Comment Operators
- Expressions
- DDL Syntax
- DML Syntax
- DCL Syntax
- SQL Syntax
- ALTER DATABASE
- ALTER FUNCTION
- ALTER PROCEDURE
- ALTER SERVER
- ALTER TABLE
- ALTER TABLE PARTITION
- ALTER TABLESPACE
- ALTER VIEW
- ANALYZE | ANALYSE
- AST
- CHECKSUM TABLE
- CREATE DATABASE
- CREATE FUNCTION
- CREATE INDEX
- CREATE PROCEDURE
- CREATE SERVER
- CREATE TABLE
- CREATE TABLE AS
- CREATE TABLE PARTITION
- CREATE TABLESPACE
- CREATE TRIGGER
- CREATE VIEW
- DESCRIBE TABLE
- DO
- DROP DATABASE
- DROP INDEX
- DROP TABLESPACE
- EXECUTE
- EXPLAIN
- FLUSH BINARY LOGS
- GRANT
- GRANT/REVOKE PROXY
- INSERT
- KILL
- LOAD DATA
- OPTIMIZE TABLE
- PREPARE
- RENAME TABLE
- RENAME USER
- REVOKE
- SELECT
- SELECT HINT
- SET CHARSET
- SET PASSWORD
- SHOW CHARACTER SET
- SHOW COLLATION
- SHOW COLUMNS
- SHOW CREATE DATABASE
- SHOW CREATE FUNCTION
- SHOW CREATE PROCEDURE
- SHOW CREATE TABLE
- SHOW CREATE TRIGGER
- SHOW CREATE VIEW
- SHOW DATABASES
- SHOW FUNCTION STATUS
- SHOW GRANTS
- SHOW INDEX
- SHOW MASTER STATUS
- SHOW PLUGINS
- SHOW PRIVILEGES
- SHOW PROCEDURE STATUS
- SHOW PROCESSLIST
- SHOW SLAVE HOSTS
- SHOW STATUS
- SHOW TABLES
- SHOW TABLE STATUS
- SHOW TRIGGERS
- SHOW VARIABLES
- SHOW WARNINGS/ERRORS
- UPDATE
- USE db_name
- System Views
- GUC Parameters
- Resetting Parameters
- Stored Procedures
- Identifiers
- SQL Reference
- MySQL Syntax Compatibility Assessment Tool
- Dolphin Extension
- Materialized View
- Partition Management
- Application Development Guide
- Performance Tuning Guide
- Reference Guide
- System Catalogs and System Views
- Overview
- Querying a System Catalog
- System Catalogs
- GS_ASP
- GS_AUDITING_POLICY
- GS_AUDITING_POLICY_ACCESS
- GS_AUDITING_POLICY_FILTERS
- GS_AUDITING_POLICY_PRIVILEGES
- GS_CLIENT_GLOBAL_KEYS
- GS_CLIENT_GLOBAL_KEYS_ARGS
- GS_COLUMN_KEYS
- GS_COLUMN_KEYS_ARGS
- GS_DB_PRIVILEGE
- GS_ENCRYPTED_COLUMNS
- GS_ENCRYPTED_PROC
- GS_GLOBAL_CHAIN
- GS_GLOBAL_CONFIG
- GS_MASKING_POLICY
- GS_MASKING_POLICY_ACTIONS
- GS_MASKING_POLICY_FILTERS
- GS_MATVIEW
- GS_MATVIEW_DEPENDENCY
- GS_MODEL_WAREHOUSE
- GS_OPT_MODEL
- GS_PACKAGE
- GS_POLICY_LABEL
- GS_RECYCLEBIN
- GS_TXN_SNAPSHOT
- GS_UID
- GS_WLM_EC_OPERATOR_INFO
- GS_WLM_INSTANCE_HISTORY
- GS_WLM_OPERATOR_INFO
- GS_WLM_PLAN_ENCODING_TABLE
- GS_WLM_PLAN_OPERATOR_INFO
- GS_WLM_SESSION_QUERY_INFO_ALL
- GS_WLM_USER_RESOURCE_HISTORY
- PG_AGGREGATE
- PG_AM
- PG_AMOP
- PG_AMPROC
- PG_APP_WORKLOADGROUP_MAPPING
- PG_ATTRDEF
- PG_ATTRIBUTE
- PG_AUTH_HISTORY
- PG_AUTH_MEMBERS
- PG_AUTHID
- PG_CAST
- PG_CLASS
- PG_COLLATION
- PG_CONSTRAINT
- PG_CONVERSION
- PG_DATABASE
- PG_DB_ROLE_SETTING
- PG_DEFAULT_ACL
- PG_DEPEND
- PG_DESCRIPTION
- PG_DIRECTORY
- PG_ENUM
- PG_EVENT_TRIGGER
- PG_EXTENSION
- PG_EXTENSION_DATA_SOURCE
- PG_FOREIGN_DATA_WRAPPER
- PG_FOREIGN_SERVER
- PG_FOREIGN_TABLE
- PG_HASHBUCKET
- PG_INDEX
- PG_INHERITS
- PG_JOB
- PG_JOB_PROC
- PG_LANGUAGE
- PG_LARGEOBJECT
- PG_LARGEOBJECT_METADATA
- PG_NAMESPACE
- PG_OBJECT
- PG_OPCLASS
- PG_OPERATOR
- PG_OPFAMILY
- PG_PARTITION
- PG_PLTEMPLATE
- PG_PROC
- PG_PUBLICATION
- PG_PUBLICATION_REL
- PG_RANGE
- PG_REPLICATION_ORIGIN
- PG_RESOURCE_POOL
- PG_REWRITE
- PG_RLSPOLICY
- PG_SECLABEL
- PG_SET
- PG_SHDEPEND
- PG_SHDESCRIPTION
- PG_SHSECLABEL
- PG_STATISTIC
- PG_STATISTIC_EXT
- PG_SUBSCRIPTION
- PG_SUBSCRIPTION_REL
- PG_SYNONYM
- PG_TABLESPACE
- PG_TRIGGER
- PG_TS_CONFIG
- PG_TS_CONFIG_MAP
- PG_TS_DICT
- PG_TS_PARSER
- PG_TS_TEMPLATE
- PG_TYPE
- PG_USER_MAPPING
- PG_USER_STATUS
- PG_WORKLOAD_GROUP
- PGXC_CLASS
- PGXC_GROUP
- PGXC_NODE
- PGXC_SLICE
- PLAN_TABLE_DATA
- STATEMENT_HISTORY
- System Views
- GET_GLOBAL_PREPARED_XACTS(Discarded)
- GS_ASYNC_SUBMIT_SESSIONS_STATUS
- GS_AUDITING
- GS_AUDITING_ACCESS
- GS_AUDITING_PRIVILEGE
- GS_CLUSTER_RESOURCE_INFO
- GS_COMPRESSION
- GS_DB_PRIVILEGES
- GS_FILE_STAT
- GS_GSC_MEMORY_DETAIL
- GS_INSTANCE_TIME
- GS_LABELS
- GS_LSC_MEMORY_DETAIL
- GS_MASKING
- GS_MATVIEWS
- GS_OS_RUN_INFO
- GS_REDO_STAT
- GS_SESSION_CPU_STATISTICS
- GS_SESSION_MEMORY
- GS_SESSION_MEMORY_CONTEXT
- GS_SESSION_MEMORY_DETAIL
- GS_SESSION_MEMORY_STATISTICS
- GS_SESSION_STAT
- GS_SESSION_TIME
- GS_SHARED_MEMORY_DETAIL
- GS_SQL_COUNT
- GS_STAT_SESSION_CU
- GS_THREAD_MEMORY_CONTEXT
- GS_TOTAL_MEMORY_DETAIL
- GS_WLM_CGROUP_INFO
- GS_WLM_EC_OPERATOR_STATISTICS
- GS_WLM_OPERATOR_HISTORY
- GS_WLM_OPERATOR_STATISTICS
- GS_WLM_PLAN_OPERATOR_HISTORY
- GS_WLM_REBUILD_USER_RESOURCE_POOL
- GS_WLM_RESOURCE_POOL
- GS_WLM_SESSION_HISTORY
- GS_WLM_SESSION_INFO
- GS_WLM_SESSION_INFO_ALL
- GS_WLM_SESSION_STATISTICS
- GS_WLM_USER_INFO
- IOS_STATUS
- MPP_TABLES
- PG_AVAILABLE_EXTENSION_VERSIONS
- PG_AVAILABLE_EXTENSIONS
- PG_COMM_DELAY
- PG_COMM_RECV_STREAM
- PG_COMM_SEND_STREAM
- PG_COMM_STATUS
- PG_CONTROL_GROUP_CONFIG
- PG_CURSORS
- PG_EXT_STATS
- PG_GET_INVALID_BACKENDS
- PG_GET_SENDERS_CATCHUP_TIME
- PG_GROUP
- PG_GTT_ATTACHED_PIDS
- PG_GTT_RELSTATS
- PG_GTT_STATS
- PG_INDEXES
- PG_LOCKS
- PG_NODE_ENV
- PG_OS_THREADS
- PG_PREPARED_STATEMENTS
- PG_PREPARED_XACTS
- PG_PUBLICATION_TABLES
- PG_REPLICATION_ORIGIN_STATUS
- PG_REPLICATION_SLOTS
- PG_RLSPOLICIES
- PG_ROLES
- PG_RULES
- PG_RUNNING_XACTS
- PG_SECLABELS
- PG_SESSION_IOSTAT
- PG_SESSION_WLMSTAT
- PG_SETTINGS
- PG_SHADOW
- PG_STAT_ACTIVITY
- PG_STAT_ACTIVITY_NG
- PG_STAT_ALL_INDEXES
- PG_STAT_ALL_TABLES
- PG_STAT_BAD_BLOCK
- PG_STAT_BGWRITER
- PG_STAT_DATABASE
- PG_STAT_DATABASE_CONFLICTS
- PG_STAT_REPLICATION
- PG_STAT_SUBSCRIPTION
- PG_STAT_SYS_INDEXES
- PG_STAT_SYS_TABLES
- PG_STAT_USER_FUNCTIONS
- PG_STAT_USER_INDEXES
- PG_STAT_USER_TABLES
- PG_STAT_XACT_ALL_TABLES
- PG_STAT_XACT_SYS_TABLES
- PG_STAT_XACT_USER_FUNCTIONS
- PG_STAT_XACT_USER_TABLES
- PG_STATIO_ALL_INDEXES
- PG_STATIO_ALL_SEQUENCES
- PG_STATIO_ALL_TABLES
- PG_STATIO_SYS_INDEXES
- PG_STATIO_SYS_SEQUENCES
- PG_STATIO_SYS_TABLES
- PG_STATIO_USER_INDEXES
- PG_STATIO_USER_SEQUENCES
- PG_STATIO_USER_TABLES
- PG_STATS
- PG_TABLES
- PG_TDE_INFO
- PG_THREAD_WAIT_STATUS
- PG_TIMEZONE_ABBREVS
- PG_TIMEZONE_NAMES
- PG_TOTAL_MEMORY_DETAIL
- PG_TOTAL_USER_RESOURCE_INFO
- PG_TOTAL_USER_RESOURCE_INFO_OID
- PG_USER
- PG_USER_MAPPINGS
- PG_VARIABLE_INFO
- PG_VIEWS
- PG_WLM_STATISTICS
- PGXC_PREPARED_XACTS
- PLAN_TABLE
- PATCH_INFORMATION_TABLE
- Functions and Operators
- Logical Operators
- Comparison Operators
- Character Processing Functions and Operators
- Binary String Functions and Operators
- Bit String Functions and Operators
- Mode Matching Operators
- Mathematical Functions and Operators
- Date and Time Processing Functions and Operators
- Type Conversion Functions
- Geometric Functions and Operators
- Network Address Functions and Operators
- Text Search Functions and Operators
- JSON/JSONB Functions and Operators
- HLL Functions and Operators
- SEQUENCE Functions
- Array Functions and Operators
- Range Functions and Operators
- Aggregate Functions
- Window Functions(Analysis Functions)
- Security Functions
- Ledger Database Functions
- Encrypted Equality Functions
- Set Returning Functions
- Conditional Expression Functions
- System Information Functions
- System Administration Functions
- Configuration Settings Functions
- Universal File Access Functions
- Server Signal Functions
- Backup and Restoration Control Functions
- Snapshot Synchronization Functions
- Database Object Functions
- Advisory Lock Functions
- Logical Replication Functions
- Segment-Page Storage Functions
- Other Functions
- Undo System Functions
- Row-store Compression System Functions
- Statistics Information Functions
- Trigger Functions
- Event Trigger Functions
- Hash Function
- Prompt Message Function
- Global Temporary Table Functions
- Fault Injection System Function
- AI Feature Functions
- Dynamic Data Masking Functions
- Other System Functions
- Internal Functions
- Global SysCache Feature Functions
- Data Damage Detection and Repair Functions
- XML Functions
- Obsolete Functions
- Supported Data Types
- SQL Syntax
- ABORT
- ALTER AGGREGATE
- ALTER AUDIT POLICY
- ALTER DATABASE
- ALTER DATA SOURCE
- ALTER DEFAULT PRIVILEGES
- ALTER DIRECTORY
- ALTER EVENT
- ALTER EVENT TRIGGER
- ALTER EXTENSION
- ALTER FOREIGN DATA WRAPPER
- ALTER FOREIGN TABLE
- ALTER FUNCTION
- ALTER GLOBAL CONFIGURATION
- ALTER GROUP
- ALTER INDEX
- ALTER LANGUAGE
- ALTER LARGE OBJECT
- ALTER MASKING POLICY
- ALTER MATERIALIZED VIEW
- ALTER OPERATOR
- ALTER PACKAGE
- ALTER PROCEDURE
- ALTER PUBLICATION
- ALTER RESOURCE LABEL
- ALTER RESOURCE POOL
- ALTER ROLE
- ALTER ROW LEVEL SECURITY POLICY
- ALTER RULE
- ALTER SCHEMA
- ALTER SEQUENCE
- ALTER SERVER
- ALTER SESSION
- ALTER SUBSCRIPTION
- ALTER SYNONYM
- ALTER SYSTEM KILL SESSION
- ALTER SYSTEM SET
- ALTER TABLE
- ALTER TABLE PARTITION
- ALTER TABLE SUBPARTITION
- ALTER TABLESPACE
- ALTER TEXT SEARCH CONFIGURATION
- ALTER TEXT SEARCH DICTIONARY
- ALTER TRIGGER
- ALTER TYPE
- ALTER USER
- ALTER USER MAPPING
- ALTER VIEW
- ANALYZE | ANALYSE
- BEGIN
- CALL
- CHECKPOINT
- CLEAN CONNECTION
- CLOSE
- CLUSTER
- COMMENT
- COMMIT | END
- COMMIT PREPARED
- CONNECT BY
- COPY
- CREATE AGGREGATE
- CREATE AUDIT POLICY
- CREATE CAST
- CREATE CLIENT MASTER KEY
- CREATE COLUMN ENCRYPTION KEY
- CREATE DATABASE
- CREATE DATA SOURCE
- CREATE DIRECTORY
- CREATE EVENT
- CREATE EVENT TRIGGER
- CREATE EXTENSION
- CREATE FOREIGN DATA WRAPPER
- CREATE FOREIGN TABLE
- CREATE FUNCTION
- CREATE GROUP
- CREATE INCREMENTAL MATERIALIZED VIEW
- CREATE INDEX
- CREATE LANGUAGE
- CREATE MASKING POLICY
- CREATE MATERIALIZED VIEW
- CREATE MODEL
- CREATE OPERATOR
- CREATE PACKAGE
- CREATE PROCEDURE
- CREATE PUBLICATION
- CREATE RESOURCE LABEL
- CREATE RESOURCE POOL
- CREATE ROLE
- CREATE ROW LEVEL SECURITY POLICY
- CREATE RULE
- CREATE SCHEMA
- CREATE SEQUENCE
- CREATE SERVER
- CREATE SUBSCRIPTION
- CREATE SYNONYM
- CREATE TABLE
- CREATE TABLE AS
- CREATE TABLE PARTITION
- CREATE TABLESPACE
- CREATE TABLE SUBPARTITION
- CREATE TEXT SEARCH CONFIGURATION
- CREATE TEXT SEARCH DICTIONARY
- CREATE TRIGGER
- CREATE TYPE
- CREATE USER
- CREATE USER MAPPING
- CREATE VIEW
- CREATE WEAK PASSWORD DICTIONARY
- CURSOR
- DEALLOCATE
- DECLARE
- DELETE
- DELIMITER
- DO
- DROP AGGREGATE
- DROP AUDIT POLICY
- DROP CAST
- DROP CLIENT MASTER KEY
- DROP COLUMN ENCRYPTION KEY
- DROP DATABASE
- DROP DATA SOURCE
- DROP DIRECTORY
- DROP EVENT
- DROP EVENT TRIGGER
- DROP EXTENSION
- DROP FOREIGN DATA WRAPPER
- DROP FOREIGN TABLE
- DROP FUNCTION
- DROP GLOBAL CONFIGURATION
- DROP GROUP
- DROP INDEX
- DROP LANGUAGE
- DROP MASKING POLICY
- DROP MATERIALIZED VIEW
- DROP MODEL
- DROP OPERATOR
- DROP OWNED
- DROP PACKAGE
- DROP PROCEDURE
- DROP PUBLICATION
- DROP RESOURCE LABEL
- DROP RESOURCE POOL
- DROP ROLE
- DROP ROW LEVEL SECURITY POLICY
- DROP RULE
- DROP SCHEMA
- DROP SEQUENCE
- DROP SERVER
- DROP SUBSCRIPTION
- DROP SYNONYM
- DROP TABLE
- DROP TABLESPACE
- DROP TEXT SEARCH CONFIGURATION
- DROP TEXT SEARCH DICTIONARY
- DROP TRIGGER
- DROP TYPE
- DROP USER
- DROP USER MAPPING
- DROP VIEW
- DROP WEAK PASSWORD DICTIONARY
- EXECUTE
- EXECUTE DIRECT
- EXPLAIN
- EXPLAIN PLAN
- FETCH
- GRANT
- INSERT
- LOCK
- MERGE INTO
- MOVE
- PREDICT BY
- PREPARE
- PREPARE TRANSACTION
- PURGE
- REASSIGN OWNED
- REFRESH INCREMENTAL MATERIALIZED VIEW
- REFRESH MATERIALIZED VIEW
- REINDEX
- RELEASE SAVEPOINT
- RESET
- REVOKE
- ROLLBACK
- ROLLBACK PREPARED
- ROLLBACK TO SAVEPOINT
- SAVEPOINT
- SELECT
- SELECT INTO
- SET
- SET CONSTRAINTS
- SET ROLE
- SET SESSION AUTHORIZATION
- SET TRANSACTION
- SHOW
- SHOW EVENTS
- SHRINK
- SHUTDOWN
- SNAPSHOT
- START TRANSACTION
- TIMECAPSULE TABLE
- TRUNCATE
- UPDATE
- VACUUM
- VALUES
- SQL Reference
- MogDB SQL
- Keywords
- Constant and Macro
- Expressions
- Type Conversion
- Full Text Search
- System Operation
- DDL Syntax Overview
- DML Syntax Overview
- DCL Syntax Overview
- Subquery
- LLVM
- Alias
- Lock
- Transaction
- Ordinary Table
- Partitioned Table
- Index
- Constraints
- Cursors
- Anonymous Block
- Trigger
- INSERT_RIGHT_REF_DEFAULT_VALUE
- Appendix
- GUC Parameters
- GUC Parameter Usage
- GUC Parameter List
- File Location
- Connection and Authentication
- Resource Consumption
- Write Ahead Log
- HA Replication
- Query Planning
- Error Reporting and Logging
- Alarm Detection
- Statistics During the Database Running
- Load Management
- Automatic Vacuuming
- Default Settings of Client Connection
- Lock Management
- Version and Platform Compatibility
- Faut Tolerance
- Connection Pool Parameters
- MogDB Transaction
- Replication Parameters of Two Database Instances
- Developer Options
- Auditing
- CM Parameters
- Backend Compression
- Upgrade Parameters
- Miscellaneous Parameters
- Wait Events
- Query
- System Performance Snapshot
- Security Configuration
- Global Temporary Table
- HyperLogLog
- Scheduled Task
- Thread Pool
- User-defined Functions
- Backup and Restoration
- DCF Parameters Settings
- Flashback
- Rollback Parameters
- Reserved Parameters
- AI Features
- Global SysCache Parameters
- Multi-Level Cache Management Parameters
- Resource Pooling Parameters
- Parameters Related to Efficient Data Compression Algorithms
- Writer Statement Parameters Supported by Standby Servers
- Data Import and Export
- Delimiter
- Appendix
- Schema
- Information Schema
- DBE_PERF
- OS
- Instance
- Memory
- File
- Object
- STAT_USER_TABLES
- SUMMARY_STAT_USER_TABLES
- GLOBAL_STAT_USER_TABLES
- STAT_USER_INDEXES
- SUMMARY_STAT_USER_INDEXES
- GLOBAL_STAT_USER_INDEXES
- STAT_SYS_TABLES
- SUMMARY_STAT_SYS_TABLES
- GLOBAL_STAT_SYS_TABLES
- STAT_SYS_INDEXES
- SUMMARY_STAT_SYS_INDEXES
- GLOBAL_STAT_SYS_INDEXES
- STAT_ALL_TABLES
- SUMMARY_STAT_ALL_TABLES
- GLOBAL_STAT_ALL_TABLES
- STAT_ALL_INDEXES
- SUMMARY_STAT_ALL_INDEXES
- GLOBAL_STAT_ALL_INDEXES
- STAT_DATABASE
- SUMMARY_STAT_DATABASE
- GLOBAL_STAT_DATABASE
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- Tool Reference
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- FAQ
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- Error Code Reference
- Description of SQL Error Codes
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- GAUSS-00001 - GAUSS-00100
- GAUSS-00101 - GAUSS-00200
- GAUSS 00201 - GAUSS 00300
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- GAUSS 00501 - GAUSS 00600
- GAUSS 00601 - GAUSS 00700
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- GAUSS 02601 - GAUSS 02700
- GAUSS 02701 - GAUSS 02800
- GAUSS 02801 - GAUSS 02900
- GAUSS 02901 - GAUSS 03000
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- GAUSS 03101 - GAUSS 03200
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- GAUSS 03301 - GAUSS 03400
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- GAUSS 03901 - GAUSS 04000
- GAUSS 04001 - GAUSS 04100
- GAUSS 04101 - GAUSS 04200
- GAUSS 04201 - GAUSS 04300
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- GAUSS 04501 - GAUSS 04600
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- GAUSS 04701 - GAUSS 04800
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- GAUSS 04901 - GAUSS 05000
- GAUSS 05001 - GAUSS 05100
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- GAUSS 05901 - GAUSS 06000
- GAUSS 06001 - GAUSS 06100
- GAUSS 06101 - GAUSS 06200
- GAUSS 06201 - GAUSS 06300
- GAUSS 06301 - GAUSS 06400
- GAUSS 06401 - GAUSS 06500
- GAUSS 06501 - GAUSS 06600
- GAUSS 06601 - GAUSS 06700
- GAUSS 06701 - GAUSS 06800
- GAUSS 06801 - GAUSS 06900
- GAUSS 06901 - GAUSS 07000
- GAUSS 07001 - GAUSS 07100
- GAUSS 07101 - GAUSS 07200
- GAUSS 07201 - GAUSS 07300
- GAUSS 07301 - GAUSS 07400
- GAUSS 07401 - GAUSS 07500
- GAUSS 50000 - GAUSS 50999
- GAUSS 51000 - GAUSS 51999
- GAUSS 52000 - GAUSS 52999
- GAUSS 53000 - GAUSS 53699
- Error Log Reference
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- A Query Error Is Reported Due to Predicate Pushdown
- Table/Partition Table Fault Location
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- File Is Damaged in the XFS File System
- Insufficient Memory
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- When the TPC-C is running and a disk to be injected is full, the TPC-C stops responding
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- Shared Memory Leakage
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- Source Code Parsing
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Backup and Restoration Control Functions
Backup Control Functions
Backup control functions help with online backup.
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pg_create_restore_point(name text)
Description: Creates a named point for performing the restoration operation (restricted to the system administrator).
Return type: text
Note: pg_create_restore_point creates a named transaction log record that can be used as a restoration target, and returns the corresponding transaction log location. The given name can then be used with recovery_target_name to specify the point up to which restoration will proceed. Avoid creating multiple restoration points with the same name, since restoration will stop at the first one whose name matches the restoration target.
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pg_current_xlog_location()
Description: Obtains the write position of the current transaction log.
Return type: text
Note: pg_current_xlog_location displays the write position of the current transaction log in the same format as those of the previous functions. Read-only operations do not require permissions of the system administrator.
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pg_current_xlog_insert_location()
Description: Obtains the insert position of the current transaction log.
Return type: text
Note: pg_current_xlog_insert_location displays the insert position of the current transaction log. The insertion point is the logical end of the transaction log at any instant, while the write location is the end of what has been written out from the server's internal buffers. The write position is the end that can be detected externally from the server. This operation can be performed to archive only some of completed transaction log files. The insert position is mainly used for commissioning the server. Read-only operations do not require permissions of the system administrator.
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gs_current_xlog_insert_end_location()
Description: Obtains the insert position of the current transaction log.
Return type: text
Note: gs_current_xlog_insert_end_location displays the insert position of the current transaction log.
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pg_start_backup(label text [, fast boolean ])
Description: Starts executing online backup (restricted to the system administrator or replication roles).
Return type: text
Note: pg_start_backup receives a user-defined backup label (usually the name of the position where the backup dump file is stored). This function writes a backup label file to the data directory of MogDB and then returns the start position of backed up transaction logs in text mode.
MogDB=# SELECT pg_start_backup('label_goes_here'); pg_start_backup ----------------- 0/3000020 (1 row)
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pg_stop_backup()
Description: Completes online backup (restricted to the system administrator or replication roles).
Return type: text
Note: pg_stop_backup deletes the label file created by pg_start_backup and creates a backup history file in the transaction log archive area. The history file includes the label given to pg_start_backup, the start and end transaction log locations for the backup, and the start and end time of the backup. The return value is the backup's ending transaction log location. After the end position is calculated, the insert position of the current transaction log automatically goes ahead to the next transaction log file. In this way, the ended transaction log file can be immediately archived so that backup is complete.
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pg_switch_xlog()
Description: Switches to a new transaction log file (restricted to the system administrator).
Return type: text
Note: pg_switch_xlog moves to the next transaction log file so that the current log file can be archived (if continuous archive is used). The return value is the ending transaction log location + 1 within the just-completed transaction log file. If there has been no transaction log activity since the last transaction log switchover, pg_switch_xlog will do nothing but return the start location of the transaction log file currently in use.
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pg_xlogfile_name(location text)
Description: Converts the position string in a transaction log to a file name.
Return type: text
Note: pg_xlogfile_name extracts only the transaction log file name. If the given transaction log position is the transaction log file border, a transaction log file name will be returned for both the two functions. This is usually the desired behavior for managing transaction log archiving, since the preceding file is the last one that currently needs to be archived.
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pg_xlogfile_name_offset(location text)
Description: Converts the position string in a transaction log to a file name and returns the byte offset in the file.
Return type: text and integer
Note: pg_xlogfile_name_offset can extract transaction log file names and byte offsets from the returned results of the preceding functions. Example:
MogDB=# SELECT * FROM pg_xlogfile_name_offset(pg_stop_backup()); NOTICE: pg_stop_backup cleanup done, waiting for required WAL segments to be archived NOTICE: pg_stop_backup complete, all required WAL segments have been archived file_name | file_offset --------------------------+------------- 000000010000000000000003 | 272 (1 row)
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pg_xlog_location_diff(location text, location text)
Description: Calculates the difference in bytes between two transaction log locations.
Return type: numeric
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pg_cbm_tracked_location()
Description: Queries the LSN location parsed by CBM.
Return type: text
-
pg_cbm_get_merged_file(startLSNArg text, endLSNArg text)
Description: Combines CBM files within the specified LSN range into one and returns the name of the combined file.
Return type: text
Note: Only the system administrator or O&M administrator can obtain the CBM combination file.
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pg_cbm_get_changed_block(startLSNArg text, endLSNArg text)
Description: Combines CBM files within the specified LSN range into a table and return records of this table.
Return type: record
Note: The table columns include the start LSN, end LSN, tablespace OID, database OID, table relfilenode, table fork number, whether the table is deleted, whether the table is created, whether the table is truncated, number of pages in the truncated table, number of modified pages, and list of modified page numbers.
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pg_cbm_recycle_file(targetLSNArg text)
Description: Delete all cbm file contents before targetLSNArg and return the first lsn after deletion.
Return type: text
Note: This function does not check whether the deleted cbm file is invalid, so it is recommended to delete at most the contents of the cbm file corresponding to the most recent backup Stop lsn. If you delete the contents of the cbm file that has not been incrementally backed up, the incremental backup function will become invalid.
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pg_cbm_force_track(targetLSNArg text,timeOut int)
Description: Forcibly executes the CBM trace to the specified Xlog position and returns the Xlog position of the actual trace end point.
Return type: text
-
pg_enable_delay_ddl_recycle()
Description: Enables DDL delay and returns the Xlog position of the enabling point. You need to enable operate_mode as the administrator or O&M administrator.
Return type: text
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pg_disable_delay_ddl_recycle(barrierLSNArg text, isForce bool)
Description: Disables DDL delay and returns the Xlog range where DDL delay takes effect. You need to enable operate_mode as the administrator or O&M administrator.
Return type: record
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pg_enable_delay_xlog_recycle()
Description: Enables Xlog recycle delay. This function is used in primary database node restoration.
Return type: void
-
pg_disable_delay_xlog_recycle()
Description: Disables Xlog recycle delay. This function is used in primary database node restoration.
Return type: void
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pg_cbm_rotate_file(rotate_lsn text)
Description: Forcibly switches the file after the CBM parses rotate_lsn. This function is called during the build process.
Return type: void
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gs_roach_stop_backup(backupid text)
Description: Stops a backup started by the internal backup tool GaussRoach. It is similar to the pg_stop_backup system function but is more lightweight.
Return type: text. The content is the insertion position of the current log.
Note: Currently, MogDB does not support this function.
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gs_roach_enable_delay_ddl_recycle(backupid name)
Description: Enables DDL delay and returns the log location of the enabling point. It is similar to the pg_enable_delay_ddl_recycle system function but is more lightweight. In addition, different backupid values can be used to concurrently open DDL statements with delay.
Return type: text. The content is the log location of the start point.
Note: Currently, MogDB does not support this function.
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gs_roach_disable_delay_ddl_recycle(backupid text)
Description: Disables DDL delay, returns the range of logs on which DDL delay takes effect, and deletes the physical files of column-store tables that are deleted by users within this range. It is similar to the pg_enable_delay_ddl_recycle system function but is more lightweight. In addition, the DDL delay function can be disabled concurrently by specifying different backupid values.
Return type: record. The content is the range of logs for which DDL is delayed to take effect.
Note: Currently, MogDB does not support this function.
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gs_roach_switch_xlog(request_ckpt bool)
Description: Switches the currently used log segment file and triggers a full checkpoint if request_ckpt is set to true.
Return type: text. The content is the location of the segment log.
Restoration Control Functions
Restoration control functions provide information about the status of standby nodes. These functions may be executed both during restoration and in normal running.
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pg_is_in_recovery()
Description: Returns true if restoration is still in progress.
Return type: bool
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pg_last_xlog_receive_location()
Description: Gets the last transaction log location received and synchronized to disk by streaming replication. While streaming replication is in progress, this will increase monotonically. If restoration has completed, this value will remain static at the value of the last WAL record received and synchronized to disk during restoration. If streaming replication is disabled or if it has not yet started, the function returns NULL.
Return type: text
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pg_last_xlog_replay_location()
Description: Gets last transaction log location replayed during restoration. If restoration is still in progress, this will increase monotonically. If restoration has completed, then this value will remain static at the value of the last WAL record received during that restoration. When the server has been started normally without restoration, the function returns NULL.
Return type: text
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pg_last_xact_replay_timestamp()
Description: Gets the timestamp of last transaction replayed during restoration. This is the time to commit a transaction or abort a WAL record on the primary node. If no transactions have been replayed during restoration, this function will return NULL. If restoration is still in progress, this will increase monotonically. If restoration has completed, then this value will remain static at the value of the last WAL record received during that restoration. If the server normally starts without manual intervention, this function will return NULL.
Return type: timestamp with time zone
Restoration control functions control restoration processes. These functions may be executed only during restoration.
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pg_is_xlog_replay_paused()
Description: Returns true if restoration is paused.
Return type: bool
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pg_xlog_replay_pause()
Description: Pauses restoration immediately.
Return type: void
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pg_xlog_replay_resume()
Description: Restarts restoration if it was paused.
Return type: void
While restoration is paused, no further database changes are applied. In hot standby mode, all new queries will see the same consistent snapshot of the database, and no further query conflicts will be generated until restoration is resumed.
If streaming replication is disabled, the paused state may continue indefinitely without problem. While streaming replication is in progress, WAL records will continue to be received, which will eventually fill available disk space. This progress depends on the duration of the pause, the rate of WAL generation, and available disk space.