What is the difference between "AND" and "&&" in MySQL?

Note: There is only one difference between AND and &&, that is, AND is a standard syntax, while && is an ownership syntax.

There is no difference between AND and && except for the above statement. Let's look at all the conditions.

AND and && always result in 1 or 0. As we all know, AND and && are both logical operators. If there are multiple operands and any one of them has a value of 0, the result is 0, otherwise it is 1.

Here is a demonstration of AND and &&.

Case 1(a): If both operands are 1. Use AND.

The query is as follows:

mysql> select 1 AND 1 as Result;

The following is the output result:

+--------+
| Result |
+--------+
|      1 |
+--------+
1 row in set (0.00 sec)

Case 1(b): If both operands are 1. use&&.

The query is as follows:

mysql> select 1 && 1 as Result;

The following is the output result:

+--------+
| Result |
+--------+
|      1 |
+--------+
1 row in set (0.00 sec)

Case 2(a): If any operand is 0, then the result is 0. Use AND.

The query is as follows:

mysql> select 1 AND 0 as Result;

The following is the output result:

+--------+
| Result |
+--------+
|      0 |
+--------+
1 row in set (0.00 sec)

Case 2(b): If any operand is 0, then the result becomes 0. use&&.

The query is as follows:

mysql> select 1 && 0 as Result;

The following is the output result:

+--------+
| Result |
+--------+
|      0 |
+--------+
1 row in set (0.00 sec)

This is a null value situation.

Case 3(a): If any operand is NULL, the result becomes NULL. Use AND.

The query is as follows:

mysql> select NULL AND 1 as Result;

The following is the output result:

+--------+
| Result |
+--------+
|   NULL |
+--------+
1 row in set (0.00 sec)

Case 3(b): If any operand is NULL, the result becomes NULL. use&&.

The query is as follows:

mysql> select NULL && 1 as Result;

The following is the output:

+--------+
| Result |
+--------+
|   NULL |
+--------+
1 row in set (0.00 sec)

Note: The situation discussed above does not rely solely on 1 and 0. Any non-zero value will be true, which means if we AND or && two negative numbers, the result will become 1.

Look at the situation with negative numbers. The query is as follows:

mysql> select -10 AND -30 as Result;
+--------+
| Result |
+--------+
|      1 |
+--------+
1 row in set (0.04 sec)
mysql> select -10 && -30 as Result;
+--------+
| Result |
+--------+
|      1 |
+--------+
1 row in set (0.00 sec)

In the above case, if any value is 0, the result becomes 0 in both AND and &&. The query is as follows:

mysql> select -10 AND 0 as Result;
+--------+
| Result |
+--------+
|      0 |
+--------+
1 row in set (0.00 sec)

Look at the positive cases. The query is as follows:

mysql> select 10 AND 30 as Result;
+--------+
| Result |
+--------+
|      1 |
+--------+
1 row in set (0.00 sec)
mysql> select 10 && 30 as Result;
+--------+
| Result |
+--------+
|      1 |
+--------+
1 row in set (0.00 sec)

Among them, if any operand becomes 0, the result becomes 0. The query is as follows:

mysql> select 10 and 0 as Result;
+--------+
| Result |
+--------+
|      0 |
+--------+
1 row in set (0.00 sec)
mysql> select 10 && 0 as Result;
+--------+
| Result |
+--------+
|      0 |
+--------+
1 row in set (0.00 sec)

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