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28 lines
840 B
C++
28 lines
840 B
C++
#include <Functions/isNotDistinctFrom.h>
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namespace DB
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{
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REGISTER_FUNCTION(IsNotDistinctFrom)
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{
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factory.registerFunction<FunctionIsNotDistinctFrom>(
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FunctionDocumentation{
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.description = R"(
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Performs a null-safe comparison between two values. This function will consider
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two `NULL` values as identical and will return `true`, which is distinct from the usual
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equals behavior where comparing two `NULL` values would return `NULL`.
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Currently, this function can only be used in the `JOIN ON` section of a query.
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[example:join_on_is_not_distinct_from]
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)",
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.examples{
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{"join_on_is_not_distinct_from", "SELECT * FROM (SELECT NULL AS a) AS t1 JOIN (SELECT NULL AS b) AS t2 ON isNotDistinctFrom(t1.a, t2.b)", "NULL\tNULL"},
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},
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.categories = {"Comparison", "Join Operators"},
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});
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}
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}
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