DB2 VIEW
对VIEW进行DML操作的时候,具体看WITH CHECK OPTION是否有,
有就按照VIEW条件过滤,否则条件无用。
CREATE VIEW v1 AS SELECT col1 FROM t1 WHERE col1 > 10;
CREATE VIEW v2 AS SELECT col1 FROM v1 WITH CASCADED CHECK OPTION;
CREATE VIEW v3 AS SELECT col1 FROM v2 WHERE col1 < 100;
v1的条件就可以无视。
v2继承了v1,所以会过滤col1>10
v3继承了v1,v2,所以会过滤col > 10,但是不会过滤col1<100
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