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The Department Table: DSN8810.DEPTDSN8810.DEPT describes information about departments that may be participating in projects. The following information is stored for each department: the department number, the department name , the employee number for the manager of this department, and the department number for the department to which this department reports . The department number is the primary key. Referential integrity is used to implement a self-referencing constraint for ADMRDEPT . This referential constraint establishes the higher level department to which this department reports. A constraint also exists for MGRNO to EMPNO , the primary key of the DSN8810.EMP table. It ensures that the manager of a department is a valid employee. Three indexes have been built for this table: DSN8810.XDEPT1 is a primary key index on DEPTNO , DSN8810.XDEPT2 is an index on MGRNO , and DSN8810.XDEPT3 is an index on ADMRDEPT . DSN8810.DEPT Table DDLCREATE TABLE DSN8810.DEPT (DEPTNO CHAR(3) NOT NULL, DEPTNAME VARCHAR(36) NOT NULL, MGRNO CHAR(6), ADMRDEPT CHAR(3) NOT NULL, LOCATION CHAR(16), PRIMARY KEY (DEPTNO) ) IN DSN8D81A.DSN8S81D CCSID EBCDIC; ALTER TABLE DSN8810.DEPT FOREIGN KEY RDD (ADMRDEPT) REFERENCES DSN8810.DEPT ON DELETE CASCADE; ALTER TABLE DSN8810.DEPT FOREIGN KEY RDE (MGRNO) REFERENCES DSN8810.EMP ON DELETE SET NULL; |
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