Programmer Think

New tablespaces and corresponding users in Oracle Database Create tablespace and temporary tablespace data files Create a tablespace data file SQL> CREATE TABLESPACE rec_news LOGGING DATAFILE '/home/oracle/OracleDB/user/rec_news/rec_news.dbf' SIZE 100M AUTOEXTEND ON NEXT 100M MAXSIZE 5120M EXTENT MANAGEMENT LOCAL; Ta ...

Parallel replication records updated from the library do not exist, but exist background The semi synchronous slave database SQL thread with parallel replication enabled reports 1032 errors, while the asynchronous slave database does not report any errors. This happens occasionally Analysis Version mysql 5.7.16 mysql> show variables like '%s ...

Introduction Dynamic SQL: dynamic SQL. In this section, we will learn from the official documents of MyBatis. Description The official description is as follows: One of the most powerful features of MyBatis has always been its Dynamic SQL capabilities. If you have any experience with JDBC or any similar framework, you understand how painful it ...

SQL consists of the following four parts: 1 data definition language (DDL): DROP, CREATE, ALTER and other statements. 2 data operation language (DML): INSERT, UPDATE and DELETE statements. 3 data query language (DQL): SELECT statement. 4 data control language (DCL): GRANT, REVOKE, COMMIT, ROLLBACK and other statements. DDL(Dat ...

The field constraint of mysql is inevitable in the future. There are four main contents as follows: the primary key constraint is used for uniqueness and cannot be empty; the non empty constraint cannot be empty and can be repeated; the unique constraint can be empty but must be unique; the foreign key constraint is to make a certain associatio ...

Summary MySQL EVENT is a scheduled task, similar to crontab task on LinuxIt mainly has the following properties In mysql, the objects of timing events are globally unique event performs operations according to the schedule, including one SQL operation. You can also use begin and end to implement multiple SQL composite execution The permission ...

1 background When using the paging function of mybatis plus (hereinafter referred to as MBP). Found a JsqlParserCountOptimize The official didn't give a detailed introduction to the paging optimization processing class of, and didn't find a few words on the Internet to analyze the logic of this class, which we dare not use. It's also convenient ...

Original Link: http://www.yiidian.com/jdbc/jdbc-callablestatement.html 1 CallableStatement interface The CallableStatement interface is used to call stored procedures and functions. By using stored procedures and functions, we can write business logic on the database, which will improve performance because they are precompiled. 2 What is the di ...

The content of the content 1. Database connection pool * concept and function         * C3P0         * Druid * Custom JDBC tool class     2. Spring JDBC : JDBC Template 3. Transaction control in Srping##Database connection pool 1. Concept: in fact, it is a container (Collection) for database connecti ...

OB Jun: good news! "Oceanbase version 2.2" is officially launched on the official website! (click to read the original text and download it directly) OceanBase 2.2 is a stable version that successfully supports tmall double 11 in 2019, and it is also the version used for TPC-C testing and ranked first in TPC-C performance. We will con ...