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@ -364,8 +364,8 @@ |
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</indexterm> |
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Ordinary comparison operators yield null (signifying <quote>unknown</>), |
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not true or false, when either input is null. For example, |
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<literal>7 = NULL</> yields null. When this behavior is not suitable, |
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use the |
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<literal>7 = NULL</> yields null, as does <literal>7 <> NULL</>. When |
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this behavior is not suitable, use the |
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<literal>IS <optional> NOT </> DISTINCT FROM</literal> constructs: |
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<synopsis> |
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<replaceable>expression</replaceable> IS DISTINCT FROM <replaceable>expression</replaceable> |
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