单选题Which of the following will be a consequence of defining the column IDCOL2 in TABLE2 as a foreign key referencing the primary key (IDCOL1) of TABLE1?（）ADB2 will no longer allow updating the value of IDCOL1 in TABLE1.BWhen inserting a row in TABLE2, the only values that DB2 will allow for IDCOL2 are the existing values of IDCOL1.CWhen inserting a row in TABLE2, DB2 will only allow foreign values for IDCOL2, that is values which do not exist in IDCOL1.DWhen a SELECT statement joins TABLE1 with TABLE2, DB2 will automatically add the condition TABLE1.IDCOL1=TABLE2.IDCOL2 if not specified in the statement.
单选题
Which of the following will be a consequence of defining the column IDCOL2 in TABLE2 as a foreign key referencing the primary key (IDCOL1) of TABLE1?（）
A
DB2 will no longer allow updating the value of IDCOL1 in TABLE1.
B
When inserting a row in TABLE2, the only values that DB2 will allow for IDCOL2 are the existing values of IDCOL1.
C
When inserting a row in TABLE2, DB2 will only allow foreign values for IDCOL2, that is values which do not exist in IDCOL1.
D
When a SELECT statement joins TABLE1 with TABLE2, DB2 will automatically add the condition TABLE1.IDCOL1=TABLE2.IDCOL2 if not specified in the statement.
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