SET

Purpose

You can use this statement to set variables.

Syntax

SET [SESSION | GLOBAL] var_and_val_list;

var_and_val_list:
  var_and_val [,var_and_val ...]

var_and_val:
   var_value {TO | =} set_expr_or_default
 | var_value = (simple_select)

Parameters

Examples

• Set a user variable a.

   obclient> SET @a = 1;
  

• Set a global system variable secure_file_priv, which specifies the path accessible when you import/export data to/from a file.

   obclient> SET GLOBAL secure_file_priv = '';
  

• Set a user variable proxy_route_policy, which specifies the routing strategy.

   obclient> SET @proxy_route_policy = 'follower_first';
  

• Use the SELECT statement to set variable values.

   obclient> CREATE TABLE tbl1(col INT);
   Query OK, 0 rows affected
  
   obclient> INSERT into tbl1 VALUES('1'),('2'),('3'),('4'),('5');
   Query OK, 5 rows affected
   Records: 5  Duplicates: 0  Warnings: 0
  
   obclient> SET @var1=(SELECT COUNT(*) FROM tbl1);
   Query OK, 0 rows affected