18 lines
298 B
Plaintext
18 lines
298 B
Plaintext
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[[esql-is_null]]
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=== `IS_NULL`
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Returns a boolean than indicates whether its input is `null`.
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[source,esql]
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----
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FROM employees
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| WHERE IS_NULL(first_name)
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----
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Combine this function with `NOT` to filter out any `null` data:
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[source,esql]
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----
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FROM employees
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| WHERE NOT IS_NULL(first_name)
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----
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