Oracle PL/SQL/Conversion Functions/COALESCE
COALESCE() returns the first non-null expression in the expression list
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Syntax: COALESCE (<exp1>,<exp2> . . . <expN>) SQL> SQL> SELECT COALESCE (NULL, NULL, "NOT NULL", NULL) test from dual; TEST
NOT NULL SQL> SQL>
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select coalesce( null, "", "A" )
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SQL> SQL> select coalesce( null, "", "A" )
2 from dual;
C - A 1 row selected. SQL> SQL> --
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select coalesce( null, sysdate )
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SQL> SQL> select coalesce( null, sysdate )
2 from dual;
COALESCE(
16-JUN-08 1 row selected. SQL> SQL> SQL> --
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