How to write not equal to a certain condition in sql

NO condition can be used in SQL if it is not equal to a certain condition. For example: not equal to a certain value: WHERE column_name <> value; not equal to the value in the list: WHERE column_name NOT IN (list); not equal to the subquery result: WHERE column_name <> (subquery).

How to write not equal to a certain condition in SQL

In SQL, not equal to a certain condition can be used The following syntax:

<code class="sql">NOT condition</code>

where condition is the condition that needs to be negated.

Example 1: Not equal to a certain value

For example, to query all records that are not equal to 10, you can use the following query:

<code class="sql">SELECT * FROM table_name WHERE column_name <> 10;</code>

Example 2: Not equal to the value in a list

To query all records that are not equal to (10, 20, 30), you can Use the following query:

<code class="sql">SELECT * FROM table_name WHERE column_name NOT IN (10, 20, 30);</code>

Example 3: Not equal to a subquery

To query all records in the results returned by the not equal to subquery, you can use the following query:

<code class="sql">SELECT * FROM table_name WHERE column_name <> (SELECT column_name FROM other_table_name WHERE condition);</code>

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