SQL Functions: NVL(), NVL2()

[jingchen2222]

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nvl

nvl(expr1, expr2)

• Returns expr2 if expr1 is null, or expr1 otherwise.

Examples:

> SELECT nvl(NULL, array('2'));
 ["2"]

nvl2

nvl2(expr1, expr2, expr3)

• Returns expr2 if expr1 is not null, or expr3 otherwise.

Examples:

> SELECT nvl2(NULL, 2, 1);
 1

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