v2.1

About MogDB
- MogDB Introduction
- Comparison Between MogDB and openGauss
- MogDB Release Notes
  - MogDB 2.1.1
  - MogDB 2.1.0
- Open Source Components
- Usage Limitations
- Terms of Use
Quick Start
- MogDB Playground
- Container-based MogDB Installation
- Installation on a Single Node
- MogDB Access
  - Use CLI to Access MogDB
    - gsql
    - pgcli
  - Use GUI to Access MogDB
    - Data Studio
    - DBeaver
  - Use Middleware to Access MogDB
    - Use WebLogic to Configure MogDB Data Sources
    - Use WebSphere to Configure MogDB Data Sources
  - Use Programming Language to Access MogDB
    - Java
    - C/C++
    - Python
    - Go
    - Rust
    - NodeJS
- Using Sample Dataset Mogila
Characteristic Description
Installation Guide
- Container Installation
- Simplified Installation Process
- Standard Installation
  - Installation Overview
  - Preparing for Installation
    - Environment Requirement
    - Modifying OS Configuration
  - Installing MogDB
  - Verifying the Installation
  - Recommended Parameter Settings
  - Uninstalling MogDB
- Manual Installation
Administrator Guide
AI Features Guide
- Overview
- Predictor: AI Query Time Forecasting
- X-Tuner: Parameter Optimization and Diagnosis
- SQLdiag: Slow SQL Discovery
- A-Detection: Status Monitoring
- Index-advisor: Index Recommendation
- DeepSQL
- AI-Native Database (DB4AI)
Security Guide
- Database Security Management
Developer Guide
- Application Development Guide
  - Development Specifications
  - Development Based on JDBC
  - Development Based on ODBC
  - Development Based on libpq
    - Development Based on libpq
    - libpq API Reference
      - Database Connection Control Functions
        Description
        PQconnectdbParams
        PQconnectdb
        PQconninfoParse
        PQconnectStart
        PQerrorMessage
        PQsetdbLogin
        PQfinish
        PQreset
        PQstatus
      - Database Statement Execution Functions
        PQclear
        PQexec
        PQexecParams
        PQexecParamsBatch
        PQexecPrepared
        PQexecPreparedBatch
        PQfname
        PQgetvalue
        PQnfields
        PQntuples
        PQprepare
        PQresultStatus
      - Functions for Asynchronous Command Processing
        Description
        PQsendQuery
        PQsendQueryParams
        PQsendPrepare
        PQsendQueryPrepared
        PQflush
      - Functions for Canceling Queries in Progress
        PQgetCancel
        PQfreeCancel
        PQcancel
      - Example
      - Connection Characters
  - Psycopg-Based Development
  - Commissioning
  - Appendices
- Stored Procedure
- User Defined Functions
- PL/pgSQL-SQL Procedural Language
- Scheduled Jobs
  - PKG_SERVICE API
- Autonomous Transaction
- Logical Replication
  - Logical Decoding
    - Overview
    - Logical Decoding by SQL Function Interfaces
- Foreign Data Wrapper
- Materialized View
  - Materialized View Overview
  - Full Materialized View
  - Incremental Materialized View
- Resource Load Management
  - Overview
  - Resource Management Preparation
Performance Tuning Guide
Reference Guide
Common Faults and Identification Guide
- Common Fault Locating Methods
- Common Fault Locating Cases
  - Core Fault Locating
  - Permission/Session/Data Type Fault Location
  - Service/High Availability/Concurrency Fault Location
  - Table/Partition Table Fault Location
    - Table Size Does not Change After VACUUM FULL Is Executed on the Table
    - An Error Is Reported When the Table Partition Is Modified
  - File System/Disk/Memory Fault Location
  - SQL Fault Location
  - Index Fault Location
Source Code Parsing
FAQs
Glossary

An Error Is Reported When the Table Partition Is Modified

Symptom

When ALTER TABLE PARTITION is performed, the following error message is displayed:

ERROR:start value of partition "XX" NOT EQUAL up-boundary of last partition.

Cause Analysis

If the ALTER TABLE PARTITION statement involves both the DROP PARTITION operation and the ADD PARTITION operation, MogDB always performs the DROP PARTITION operation before the ADD PARTITION operation regardless of their orders. However, performing DROP PARTITION before ADD PARTITION causes a partition gap. As a result, an error is reported.

Procedure

To prevent partition gaps, set END in DROP PARTITION to the value of START in ADD PARTITION. The following is an example:

-- Create a partitioned table partitiontest.
mogdb=#  CREATE TABLE partitiontest
(
c_int integer,
c_time TIMESTAMP WITHOUT TIME ZONE
)
PARTITION BY range (c_int)
(
partition p1 start(100)end(108),
partition p2 start(108)end(120)
);
-- An error is reported when the following statements are used:
mogdb=#  ALTER TABLE partitiontest ADD PARTITION p3 start(120)end(130), DROP PARTITION p2;
ERROR:  start value of partition "p3" NOT EQUAL up-boundary of last partition.
mogdb=#  ALTER TABLE partitiontest DROP PARTITION p2,ADD PARTITION p3 start(120)end(130);
ERROR:  start value of partition "p3" NOT EQUAL up-boundary of last partition.
-- Change them as follows:
mogdb=#  ALTER TABLE partitiontest ADD PARTITION p3 start(108)end(130), DROP PARTITION p2;
mogdb=#  ALTER TABLE partitiontest DROP PARTITION p2,ADD PARTITION p3 start(108)end(130);