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pt-table-checksum and pt-table-sync, the former is mainly used to verify the consistency of master and slave, and the latter is mainly used to repair data. The combination of the two can repair the problem of data inconsistency. 1. pt-table-checksum installation The latest address for downloading the toolkit is as follows: https://www.percona. ...

The following applies to oracle 10.2.0.5 and above One query is slow, and the original SQL is as follows: 1 select 2 a.* 3 from (select 4 ssi.ID, 5 'small_station_info' TB, 6 (select sbi.name 7 from scene_base_info sbi 8 where sbi.id = ssi.antenna_selection) as antenna_selec ...

Previously, we introduced the preliminary learning of SQLite, learned how to build tables, and how to add, delete and modify the contents of tables. This article will study SQLite in depth. SQLite constraints Since I began to learn the basic knowledge of Oracle database, I have some preliminary understanding of constraints. Constraints are ...

ABSTRACT: The result interface developed with MFC is too ugly to be seen by pass, requiring redevelopment with C >._ Previously, using MFC to develop the result interface was too ugly to be pass, requiring C# to redevelop > <, but finally got rid of the pain of VC6.0 and operated Y.   First connect to the database. (1) mysql-conn ...

Page Helper is used to paginate with mybatis and Page Interceptor is used to understand the interceptor of mybatis. Mybatis version is 3.4.6, and Mybatis Helper version is 5.1.3. 1,PageInterceptor Start with the previous code, List-1 as follows:     List-1 @Test public void testPage() { PageHelper.startPage(2, 3); List<Person ...

Simple use In the previous article, we have learned how to call mysql database without using orm. In this article, we will look at Gorm's source code, starting with the simplest query statement. Of course, Gorm's functions support where conditions, foreign key group s, and so on. The general process of these functions is almost from a simple po ...

Introduction of Singular Value Decompositionsingular value decomposition (SVD) can be understood as: a more complex matrix is represented by the multiplication of three smaller and simpler sub-matrices, which describe the important characteristics of large matrices. SVD has many uses, such as LSA (implicit semantic analysis), recommendation sys ...

Network Connection Connection The network connection part is a very important part of cobar, which takes on both forward (user-oriented) and backward (mysql-oriented) connections.By analyzing the network connection code, you can roughly see the data flow direction of cobar. Let's first look at the entire connection architecture (omit heartbe ...

2009 Unicorn Enterprise Heavy Money Recruitment Python Engineer Standard > >   Data integrity is the logical consistency an ...

Introduction to PLSQL PLSQL is an extension of Oracle to SQL99. Basically every database will extend SQL. Oracle's extension to SQL is called PLSQL. What is SQL99 (1) Rules for operating all relational databases (2) It is the fourth generation language. (3) It is a structured query language (4) Only by issuing legitimate and reasonable o ...