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SET. The SET command is used with UPDATE to specify which columns and values that should be updated in a table. The following SQL updates the first customer (CustomerID = 1) with a new ContactName and a new City:
Example. SET @name = 'John Doe'; SELECT @name; Output. +-----------+. | @name |. +-----------+. | John Doe |. +-----------+. Explanation. The SET command in the SQL statement is used to assign a value to the variable @name. The SELECT command is then executed to display the value of the @name variable, which in this case is ‘John Doe’. Example.
SET Statement Assigns a new value to a previously declared variable. The new value does not need to be of the same type as the previous value. It is an error to assign a value to an undeclared variable. Use the DECLARE statement to declare variables. Syntax. SET variable-name = new-value; Parameters. variable-name: identifier
25 Σεπ 2023 · In SQL, the 'SET' statement is a command used to modify the values of specified columns in a table. It's commonly used in conjunction with the UPDATE statement to update existing records within the table.
SQL set operations combine the results of multiple query blocks into a single result. A query block, sometimes also known as a simple table, is any SQL statement that returns a result set, such as SELECT.MySQL 9.1 also supports TABLE and VALUES statements. See the individual descriptions of these statements elsewhere in this chapter for additional information.
Normally, you search for SET values using the FIND_IN_SET() function or the LIKE operator: mysql> SELECT * FROM tbl_name WHERE FIND_IN_SET('value',set_col)>0; mysql> SELECT * FROM tbl_name WHERE set_col LIKE '%value%'; The first statement finds rows where set_col contains the value set member.
19 Φεβ 2024 · A set operation is one that combines the results of multiple query blocks into one. For example, we could combine the result of two separate SELECT statements. The results are displayed in a single result set as though we’d run a single query.
