Does double equal sign exist in MySQL?

There is no concept of double equal sign. It can be used to compare two values. If you use double equal signs (==) in MySQL, you will get an error message.

Let us verify whether this concept is correct. Declare a variable −

mysql> set @Number=10;
Query OK, 0 rows affected (0.00 sec)

Now, compare the above variable value with 10. The result will be 1 if the two values ​​are the same, 0 otherwise.

Use double equal sign -

mysql> select 10==@Number;

This will produce the following output i.e. error -

ERROR 1064 (42000): You have an error in your SQL syntax; 
check the manual that corresponds to your MySQL server version 
for the right syntax to use near '==@Number' at line 1

Let us now change the double equal sign (==) to single equal sign (=)−

mysql> select 10=@Number;

This will produce the following output-

+------------+
| 10=@Number |
+------------+
| 1          |
+------------+
1 row in set (0.00 sec)

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