How to write not equal in mysql
MySQL There are two ways to write inequalities: the inequality sign (<>) and the inequality keyword (NOT EQUAL TO). The two writing methods have the same function. You can use <> to compare whether two values are not equal, such as: SELECT FROM table_name WHERE column_name <> value; you can also use NOT EQUAL TO, such as: SELECT FROM table_name WHERE column_name NOT EQUAL TO value.
How to write the inequality operator in MySQL
There are two ways to write the inequality operator in MySQL:
- Not equal to: <>
For example:
SELECT * FROM table_name WHERE column_name < ;> value;
- Not equal to keywords: NOT EQUAL TO
For example:
SELECT * FROM table_name WHERE column_name NOT EQUAL TO value;
These two writing methods have the same function and can be used to compare whether two values are not equal.
Example
The following query finds all records in the table_name
table where column_name
is not equal to value
:
SELECT * FROM table_name WHERE column_name <> value;
The following query finds all records in the table_name
table where column_name
is not equal to value
:
SELECT * FROM table_name WHERE column_name NOT EQUAL TO value;
Note:
Unlike other relational database management systems (such as Oracle), MySQL does not support the !=
operator.
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