47 lines
853 B
Plaintext
47 lines
853 B
Plaintext
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[role="xpack"]
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[testenv="basic"]
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[[sql-functions-conditional]]
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=== Conditional Functions
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Functions that return one of their arguments by evaluating in an if-else manner.
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[[sql-functions-conditional-coalesce]]
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==== `COALESCE`
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.Synopsis
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[source, sql]
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----
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COALESCE ( expression<1>, expression<2>, ... )
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----
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*Input*:
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<1> 1st expression
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<2> 2nd expression
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...
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**N**th expression
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COALESCE can take an arbitrary number of arguments.
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*Output*: one of the expressions or `null`
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.Description
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Returns the first of its arguments that is not null.
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If all arguments are null, then it returns `null`.
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["source","sql",subs="attributes,callouts,macros"]
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----
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include-tagged::{sql-specs}/docs.csv-spec[coalesceReturnNonNull]
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----
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["source","sql",subs="attributes,callouts,macros"]
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----
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include-tagged::{sql-specs}/docs.csv-spec[coalesceReturnNull]
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----
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