mariadb function return table

MySQL Log category:General query logs: log, general_log, log_outputSlow query log: the query execution time exceeds the specified query time, that is, the slow query;Error Log: generally refers to the error log information, usually the log

Under CentOS7, the official MySQL RPM package is mariadb and can be viewed MARIADB package information[Email protected] ~]$RPM- qi mariadb # requires first installing the package NAME:MARIADB # Name epoch:1Version:5.5.52 # VersionRelease:1. EL7 #

Environment: Classroom, default lftp IP address: 172.16.0.1 Binary based programs must be installed in the/usr/local directory, and the extracted directory must be called MySQL Lftp 172.16.0.1 get to Mariadb-5.5.36 installation package

Database structure Model Classification 1, hierarchical Model 2, mesh Model 3, relational model of the relationship model components Two-dimensional relationship Table Row Column Index

In a relational database, if you want to design a table mechanism to store data, you must satisfy the basic paradigm, at least the first three paradigms.First normal form (1NF): Refers to a domain (Domain representative field) added in the

FunctionA function is to encapsulate a piece of code in a struct, and invoke the struct (function) directly when it is necessary to execute the code. This operation enables the reuse of code. In MySQL, there are two kinds of functions: system

Query cache:Cached data: k/v, which is a key-value pair;Key: The hash value of the query statement;Value: Query result of query statement;To determine whether the cache hits the standard:By comparing the hash value of the whole query statement, the

There are several types of variables in MYSQL/MARIADB: User-defined variables, system variables, general temporary variables (local variables, or local variables).1. User VariablesUser variables are session-based and user-based, so I think it's more

Translation: last_value () function (submitted to the MariaDB official Manual), last_valuemariadb This article is the translation of LAST_VALUE () in mariadb's official manual. Original article:

Execution path of the query SQL statements Query cache Parser Parse tree Pretreatment Find the best query path Query optimization SQL statements Execution plan API call Storage Engine Call data, return