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1 lut 2010 · How do I update a table and set different values upon the condition evaluating to True. For instance : UPDATE Table SET A = '1' IF A > 0 AND A < 1 SET A = '2' IF A > 1 AND A < 2 WHERE A IS NOT NULL;
In this article, we would like to show you UPDATE query with IF condition in MySQL. Quick solution: UPDATE `table_name` SET `column_name` = IF(condition , if_true, if_false); Practical example. To show UPDATE query with IF condition, we will use the following users table:
The MySQL UPDATE Statement. The UPDATE statement is used to modify the existing records in a table. UPDATE Syntax. UPDATE table_name. SET column1 = value1, column2 = value2, ... WHERE condition; Note: Be careful when updating records in a table! Notice the . WHERE clause in the UPDATE statement.
For example, if the table contains 1 and 2 in the id column and 1 is updated to 2 before 2 is updated to 3, an error occurs. To avoid this problem, add an ORDER BY clause to cause the rows with larger id values to be updated before those with smaller values: UPDATE t SET id = id + 1 ORDER BY id DESC;
16 kwi 2016 · However, given how the conditions are re-used in your UPDATE statement, you could also take a different approach altogether: represent the affected IDs and the new values as a derived table and use an update with a join:
15 mar 2012 · update table set a = if(a > 20, 20, if(a < 20 && a > 1, a, 0)) where a is not null; Add the && A > 1 to the second IF statement and your third condition is satisfied. Edit:
UPDATE is a DML statement that modifies rows in a table. An UPDATE statement can start with a WITH clause to define common table expressions accessible within the UPDATE. See Section 13.2.15, “WITH (Common Table Expressions)” . Single-table syntax: UPDATE [LOW_PRIORITY] [IGNORE] table_reference . SET assignment_list . [WHERE where_condition]
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powiązane z: mysql update if condition function error in tableCorrelate MySQL Performance Metrics With Metrics And Events From The Rest Of Your Stack. Troubleshoot Performance Issues Faster With Metrics, Traces, And Logs All In One Platform.