mysql set variable from select
One way to set a user-defined variable is by issuing a SET statement: ... mysql> SET @v3 = CAST(b'1000001' AS UNSIGNED); mysql> SELECT @v1, @v2, @v3 ... ,SET @name = 43; SET @total_tax = (SELECT SUM(tax) FROM taxable_transactions);. As demonstrated by those statements, expr can range from simple (a literal ... ,SET @counter := 100;. The second way to assign a value to a variable is to use the SELECT statement. In this case, you must use the := assignment ... ,To ensure that the query always returns maximum one row, you use the LIMIT 1 clause to limit the result set to a single row. MySQL SELECT INTO Variable ... ,From the docs (with my emphasis):. As a general rule, other than in SET statements, you should never assign a value to a user variable and read the value within ... , You can do this, as follows: SELECT @customerId := `id`, @customerName := `name` FROM customers WHERE id = 'some value';. The query ..., The issue is that you cannot mix select and set in one statement, there'll surely be syntax error: select*from t where 1 and set@a=1;. ERROR ..., SELECT salary INTO @variable1 FROM employee_info WHERE emp_id = 12345678 LIMIT 1;. or. SET @variable1 = (SELECT salary FROM ..., Yes, but you need to move the variable assignment into the query: SET @user := 123456; SELECT @group := `group` FROM user WHERE ...,You can assign a value returned by a SELECT statement to a user-defined variable, and then refer to the variable later in your mysql session. This provides a ...
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 mysql set variable from select 相關參考資料
9.4 User-Defined Variables - MySQL :: Developer Zone
One way to set a user-defined variable is by issuing a SET statement: ... mysql> SET @v3 = CAST(b'1000001' AS UNSIGNED); mysql> SELECT @v1, @v2, @v3 ... https://dev.mysql.com 13.7.4.1 SET Syntax for Variable Assignment - MySQL ...
SET @name = 43; SET @total_tax = (SELECT SUM(tax) FROM taxable_transactions);. As demonstrated by those statements, expr can range from simple (a literal ... https://dev.mysql.com MySQL Variables - MySQL Tutorial
SET @counter := 100;. The second way to assign a value to a variable is to use the SELECT statement. In this case, you must use the := assignment ... https://www.mysqltutorial.org MySQL SELECT INTO Variable - MySQL Tutorial
To ensure that the query always returns maximum one row, you use the LIMIT 1 clause to limit the result set to a single row. MySQL SELECT INTO Variable ... https://www.mysqltutorial.org Setting variables in SELECT statement mysql - Stack Overflow
From the docs (with my emphasis):. As a general rule, other than in SET statements, you should never assign a value to a user variable and read the value within ... https://stackoverflow.com Mysql set local variable in the select statement and return ...
You can do this, as follows: SELECT @customerId := `id`, @customerName := `name` FROM customers WHERE id = 'some value';. The query ... https://stackoverflow.com SET a variable in SELECT statement - MySQL - Stack Overflow
The issue is that you cannot mix select and set in one statement, there'll surely be syntax error: select*from t where 1 and set@a=1;. ERROR ... https://stackoverflow.com Set the result of a query to a variable in MySQL - Stack Overflow
SELECT salary INTO @variable1 FROM employee_info WHERE emp_id = 12345678 LIMIT 1;. or. SET @variable1 = (SELECT salary FROM ... https://stackoverflow.com MySQL: Set user variable from result of query - Stack Overflow
Yes, but you need to move the variable assignment into the query: SET @user := 123456; SELECT @group := `group` FROM user WHERE ... https://stackoverflow.com Using User-Defined Variables in SQL Statements - MySQL ...
You can assign a value returned by a SELECT statement to a user-defined variable, and then refer to the variable later in your mysql session. This provides a ... https://www.oreilly.com |