How to express not equal in sql

You can use "<>" or "!=" symbols in SQL to indicate inequality. These two symbols are used to check whether a field is not equal to a specified "value".

In SQL, it means not equal

In SQL, not equal can use "<>" or "!=" symbol indicates.

Use<>

SELECT * FROM table_name WHERE column_name <> value;

Use !=

SELECT * FROM table_name WHERE column_name != value;

Both symbols can be used to check fields Is not equal to the specified "value".

Example

In the following example, we use the "<>" symbol to query all records in the "customers" table where the "age" field is not equal to 30:

SELECT * FROM customers WHERE age <> 30;

If the "customers" table has the following data:

id	name	age
1	John	30
2	Mary	25
3	Bob	35
4	Alice	28

Then the above query will return the following results:

id	name	age
2	Mary	25
4	Alice	28

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