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Write before: Recently, the old project has added the need of daily report optimization. Li Jie asked me to use triggers to update the daily report data when inserting or updating data. Mm-hmm-hmm. when I was learning database, I met triggers, but they all jumped by, and I didn't really practice them. This time, I have the right to learn again~ ...

1. PlSql programming procedure language In the sql statement of database, the common definition of variable condition judgment cycle structure is added to the statement of process 1) . basic grammatical structure declare – declaration part – similar to defining variables begin &nda ...

Some very good enterprise level functions of the database are "military for a thousand days, military for a while". For example, the Recycle Bin function in Oracle 10g can play the role of special soldiers in special circumstances. For example, when you delete a table space or a user schema, you may delete many tables, including some ...

MySQL introduction /* MySQL database management system (file management system in essence) Advantages over ordinary files: 1. Easy to manage data; 2. Suitable for complex multi-threaded operations In MySQL: database database (essentially folder) Create database: name of create database; Display dat ...

Over() parsing function Note: aggregate functions (such as sum(), max(), etc.) can calculate some aggregate value based on a group, but aggregate functions can only return one row of records for a group. If you want to return multiple rows of records for a group, you need to use an analysis function. rank()/dense_rank over(partition by ... orde ...

Azure configuration management series Oracle Linux (PART1) Azure configuration management series Oracle Linux (PART3) 3 install desktop package in Oracle Linux When the Oracle Linux VM starts and runs, connect to it through an SSH session.   Figure 6: Oracle Linux VM started and running To log in to the system, use the same credentials that w ...

This is a magical development interface! It supports access to mysql, sqlite, Dream and oracle databases! It provides a unified C++ abstract interface externally, hides the internal implementation details, and has a learning cost of 0 for users! It provides abstract result table objects (result_ta ...

1. Add, delete, modify and check. 1, For the add operation, if the id is generated automatically, the primary key needs to be returned. Note that if the primary key is of Long type, the int type should also be returned, because mybatis does not support Long.   mybatis ResultMap application My ...

Chapter 3 Using MySQL Article Directory Chapter 3 Using MySQL Connect Select Database Understanding databases and tables Summary Simple Records - MySQL will always - [English]Ben Forta You'll learn how to connect to and log in to MySQL, how to execute MySQL statements, and how to get information ...

1. About testing Recently oracle held a series of online sharing, one of the new features of 19c is automatic indexing. I tested it in docker and failed. [oracle@8aa96a41b58b ~]$ sqlplus / as sysdba SQL*Plus: Release 19.0.0.0.0 - Production on Thu Feb 20 09:44:52 2020 Version 19.3.0.0.0 SQL> EXEC DBMS_AUTO_INDEX.CONFIGURE('AUTO_INDEX_MODE ...