What is the "where 1=1" statement in MySQL?

In MySQL, "Where 1=1" produces all rows in the table because the statement is always true. one To better understand the statement, the example is given below -

First, create a table with the help of create command. The following is given -

mysql> CREATE table WhereConditon
-> (
-> id int,
-> name varchar(100)
-> );
Query OK, 0 rows affected (0.43 sec)

After successfully creating the table, insert some records through the insert command The query for this is as follows -

mysql> INSERT into WhereConditon values(1,'John');
Query OK, 1 row affected (0.16 sec)

mysql> INSERT into WhereConditon values(2,'Smith');
Query OK, 1 row affected (0.15 sec)

mysql> INSERT into WhereConditon values(3,'Bob');
Query OK, 1 row affected (0.16 sec)

mysql> INSERT into WhereConditon values(4,'David');
Query OK, 1 row affected (0.13 sec)

Now the record is inserted successfully and you can see the number of records in the table Check with the help of select statement. Given below -

mysql> SELECT * from WhereConditon;

After executing the above query, you can see all the records in the table as follows -

+------+-------+
| id   | name  |
+------+-------+
| 1    | John  |
| 2    | Smith |
| 3    | Bob   |
| 4    | David |
+------+-------+
4 rows in set (0.00 sec)

Now, statement 1=1 is used with select statement to display table. All the names will be displayed as 1=1 is always true.

The query for this is as follows -

mysql> select name from WhereConditon where 1=1;

The following is the output of the above query

+-------+
| name  |
+-------+
| John  |
| Smith |
| Bob   |
| David |
+-------+
4 rows in set (0.00 sec)

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