CONCAT_WS

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Syntax

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Scalar

concat_ws(separator [, value, ...])

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Arguments

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Returns

• Type: STRING
• Possible values: The retained strings in argument/array order, joined with the separator.
• NULL behavior: Returns NULL for a NULL separator. NULL values and NULL array elements are skipped.

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Properties

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Usage notes

• Empty strings are retained as values, so they can produce adjacent separators.

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Examples

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NULL values are skipped

SELECT concat_ws('-', 'a', CAST(NULL AS STRING), 'b') AS "value";

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Empty strings are retained

SELECT concat_ws('-', 'a', '', 'b') AS with_empty_string, concat_ws('-', 'a', CAST(NULL AS VARCHAR), 'b') AS with_null;