NVL

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Compatibility
NVL(f1, f2)
EngineOKAlternative
ingresNoCOALESCE(f1, f2)
mysqlNoCOALESCE(f1, f2)
oracleYesCOALESCE(f1, f2)
postgresNoCOALESCE(f1, f2)
sqlserverNoCOALESCE(f1, f2)

NVL

NVL takes two arguments and returns the first value that is not null.

   NVL(x,y) = x if x is not NULL
   NVL(x,y) = y if x is NULL

NVL can be useful when you want to replace a NULL value with some other value. In this example you show the name of the party for each MSP that has a party. For the MSP with no party (such as Canavan, Dennis) you show the string None.

SELECT name, party
      ,NVL(party,'None') AS aff
  FROM gisq.msp WHERE name LIKE 'C%'
SELECT name, party
      ,COALESCE(party,'None') AS aff
  FROM msp WHERE name LIKE 'C%'

See also