# Array Comparisons¶

This section contains several constructs that can be used to make comparisons between a list of values. Comparison operations result in a boolean value (`true`/`false`) or `null`.

These Comparison Operators are supported for doing array comparisons.

For additional examples of row comparisons, see Subquery Expressions.

## `IN (value [, ...])`¶

Syntax:

```expression IN (value [, ...])
```

The binary operator `IN` allows you to verfiy the membership of the left-hand operand in the right-hand parenthesized list of scalar expressions.

Returns `true` if any of the right-hand expression is found in the result of the left-hand expression. It returns `false` otherwise.

Here’s an example:

```cr> select 1 in (1,2,3), 4 in (1,2,3);
+------------------+------------------+
| (1 IN (1, 2, 3)) | (4 IN (1, 2, 3)) |
+------------------+------------------+
| TRUE             | FALSE            |
+------------------+------------------+
SELECT 1 row in set (... sec)
```

The result of the `IN` construct yields `null` if:

• The left-hand expression evaluates to `null`, and
• There are no equal right-hand values and at least one right-hand value yields `null`

## `ANY/SOME (array expression)`¶

Syntax:

```expression operator ANY | SOME (array expression)
```

The `ANY` construct returns `true` if the defined comparison is `true` for any of the values on the right-hand side array expression. It returns `false` if the values in the array expression do not match with the provided comparison.

For example:

```cr> select 1 = any ([1,2,3]), 4 = any ([1,2,3]);
+------------------+------------------+
| 1 = ANY([1,2,3]) | 4 = ANY([1,2,3]) |
+------------------+------------------+
| TRUE             | FALSE            |
+------------------+------------------+
SELECT 1 row in set (... sec)
```

The result of the `ANY` construct yields `null` if:

• Either the expression or the array is `null`, and
• No `true` comparison is obtained and any element of the array is `null`

Note

The following is not supported by the `ANY` operator:

• `is null` and `is not null` as `operator`
• Arrays of type `object`
• Objects as `expressions`

Tip

When using `NOT <value> = ANY(<array_col>)` the performance of the query could be quite bad, because special handling is required to implement the 3-valued logic. To achieve better performance, consider using the ignore3vl function.