Home Database SQL What are the commonly used SQL statements?

What are the commonly used SQL statements?

Jun 10, 2019 pm 04:38 PM

What are the commonly used SQL statements?

Commonly used sql statements

1. Database related

Check all databases

 show databases
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Create database

create database db1
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View database

show create database db1
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Create database and specify character set

create database db1 character set utf8/gbk
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Delete database

drop database db1
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Use database

use db1
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Table related

Create table

 create table t1(id int,name varchar(10))
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View all tables

show tables
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View single table attributes

show create table t1
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View table fields

desc t1
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Create a table and specify the engine and character set

create table t1(id int,name varchar(10)) engine=myisam/innodb charset=utf8/gbk
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Modify the table

Modify the table name

rename table t1 to t2
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Modify the table attributes

alter table t1 engine=myisam/innodb charset=utf8/gbk
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Add table field

alter table t1 add age int first/after xxx
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Delete table field

alter table t1 drop age
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Modify table field name and type

alter table t1 change age newAge int
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Modify table type and location

alter table t1 modify age int first/after xx
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Delete Table

drop table t1
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