How to Drop a Unique Key Constraint in MySQL Using phpMyAdmin?

Dropping a Unique Key Constraint from a MySQL Table

A unique key constraint enforces that a column's value is distinct within a table. Occasionally, it becomes necessary to remove this constraint. Using phpMyAdmin, this process can be accomplished through a series of steps.

Step 1: Identify the Index Name

Start by retrieving the unique key constraint's associated index name. Execute the following SQL query in phpMyAdmin:

<code class="sql">SHOW INDEX FROM tbl_name;</code>

Locate the row corresponding to the unique key constraint and note its key_name.

Step 2: Drop the Index Using DROP INDEX

With the index name known, you can remove the unique key constraint using the DROP INDEX statement:

<code class="sql">DROP INDEX index_name ON tbl_name;</code>

Step 3: Alternatively, Use ALTER TABLE

You can also drop the index using the ALTER TABLE syntax:

<code class="sql">ALTER TABLE tbl_name DROP INDEX index_name;</code>

Once executed, the unique key constraint will be removed from the specified column, allowing duplicate values to be stored.

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