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  1. 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;

  2. 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:

  3. UPDATE my_table SET comments = IF(comments>3, comments-3, 0) WHERE something = 123; or a CASE expression: UPDATE my_table SET comments = CASE WHEN comments>3 THEN comments-3 ELSE 0 END WHERE something = 123;

  4. The WHERE clause, if given, specifies the conditions that identify which rows to update. With no WHERE clause, all rows are updated. If the ORDER BY clause is specified, the rows are updated in the order that is specified. The LIMIT clause places a limit on the number of rows that can be updated.

  5. What is a NULL Value? A field with a NULL value is a field with no value. If a field in a table is optional, it is possible to insert a new record or update a record without adding a value to this field. Then, the field will be saved with a NULL value.

  6. 29 maj 2017 · Is it possible to do UPDATE query on MySQL which updates field value only if certain condition is met? Something like this: UPDATE test. SET. CASE. WHEN true. THEN field = 1. END. WHERE id = 123. In other words, "field" would be only updated if condition is met, otherwise nothing is done.

  7. 17 maj 2024 · Updating a column with a NULL value in MySQL is surprisingly straightforward. Check out this basic syntax: UPDATE table_name. SET column_name= 'N/A' WHERE condition; table_name: The name of your table. column_name: The column you want to turn into NULL. condition: When you want to be selective. If you skip this, it'll update all rows.

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