How to Update a Column in MySQL Without Affecting Other Columns?

Performing Column Updates in MySQL

To modify a column in a table, it is crucial to utilize appropriate SQL commands. In this instance, altering the contents of a column without affecting other columns requires an update operation.

UPDATE vs. INSERT: Understanding the Difference

The scenario described involves altering the values of the col_a column. This cannot be accomplished using an INSERT statement, as it serves to insert new rows into a table. Instead, the UPDATE command should be employed, which enables modifications to existing data.

Using the UPDATE Command

The syntax of the UPDATE command is as follows:

UPDATE table_name SET column_name = new_value WHERE condition;

Specific Example: Updating 'col_a' Column

To update the col_a column specifically, the following commands can be used:

UPDATE table1 SET col_a='foo' WHERE key_col='k1';
UPDATE table1 SET col_a='bar' WHERE key_col='k2';

By utilizing these commands, the values of the col_a column for the rows with key_col values of 'k1' and 'k2' will be updated to 'foo' and 'bar', respectively.

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