MySQL statements commonly used in PHP

MySQL statements are often used in PHP development. The following lists some frequently used MySQL statements, hoping to play a role in your daily learning and development work.

MySQL statements display databases or tables:
Show databases; // you can then use database_name;
Show tables;

MySQL statement to change the table name:
Alter table table_name rename new_t;

Add a column in a MySQL statement:
Alter table table_name add column c_n column attributes;

MySQL statement:
Alter table table_name drop column c_n;

Create an index using a MySQL statement:
Alter table c_table add index (c_n1, c_n2 );
Alter table c_table add unique index_name (c_n );
Alter table c_table add primary key (sid );

MySQL statement to delete an index:
Alter table c_table drop index c_n1;

MySQL statement to change column information:
Alter table t_table change c_1 c_1 varchar (200 );
Alter table t_table modify 1 c_1 varchar (200 );

Insert statement:
Insert into table_name (c_1, c_2)
Values ('x1', 1 );

Update statement:
Update table_name set c_1 = 1 where c_2 = 3;

MySQL statement to delete a database or table:
Drop table table_name;
Drop database database_name; // data that can be deleted using mysql_drop_db.
 

How to use mysql UPDATE statements

Use case when statement in mysql

How to update some data in a Mysql Field

Mysql inserts an instance of the Clob Field

Length of int data type in mysql