SQL中,下列涉及空值的操作,正确的是
AWHERE AGE IS NULL
BWHERE AGE IS NOT NULL
CWHERE AGE = NULL
DWHERE NOT (AGE IS NULL)
SQL中,下列涉及空值的操作,正确的是
AWHERE AGE IS NULL
BWHERE AGE IS NOT NULL
CWHERE AGE = NULL
DWHERE NOT (AGE IS NULL)
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