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90 lines
1.3 KiB
Markdown
90 lines
1.3 KiB
Markdown
---
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slug: /en/sql-reference/functions/comparison-functions
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sidebar_position: 35
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sidebar_label: Comparison
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---
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# Comparison Functions
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Below comparison functions return 0 or 1 as Uint8.
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The following types can be compared:
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- numbers
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- strings and fixed strings
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- dates
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- dates with times
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Only values within the same group can be compared (e.g. UInt16 and UInt64) but not across groups (e.g. UInt16 and DateTime).
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Strings are compared byte-by-byte. Note that this may lead to unexpected results if one of the strings contains UTF-8 encoded multi-byte characters.
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A string S1 which has another string S2 as prefix is considered longer than S2.
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## equals, `=`, `==` operators {#equals}
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**Syntax**
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```sql
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equals(a, b)
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```
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Alias:
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- `a = b` (operator)
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- `a == b` (operator)
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## notEquals, `!=`, `<>` operators {#notequals}
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**Syntax**
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```sql
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notEquals(a, b)
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```
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Alias:
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- `a != b` (operator)
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- `a <> b` (operator)
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## less, `<` operator {#less}
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**Syntax**
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```sql
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less(a, b)
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```
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Alias:
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- `a < b` (operator)
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## greater, `>` operator {#greater}
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**Syntax**
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```sql
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greater(a, b)
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```
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Alias:
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- `a > b` (operator)
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## lessOrEquals, `<=` operator {#lessorequals}
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**Syntax**
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```sql
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lessOrEquals(a, b)
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```
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Alias:
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- `a <= b` (operator)
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## greaterOrEquals, `>=` operator {#greaterorequals}
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**Syntax**
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```sql
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greaterOrEquals(a, b)
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```
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Alias:
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- `a >= b` (operator)
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