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??Oracle?????????????
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CREATE TABLE department(  deptno NUMBER(2) PRIMARY KEY,  dname VARCHAR(20) NOT NULL);
CREATE TABLE project(  proid NUMBER(4) PRIMARY KEY,  proname VARCHAR2(50) NOT NULL,  prodate DATE NOT NULL,  deptno NUMBER(2),  CONSTRAINT department_project_deptno FOREIGN KEY(deptno) ON DELETE CASCADE);
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CREATE TYPE project_ty AS OBJECT(  proid NUMBER(4),  proname VARCHAR2(50),  prodate DATE);
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CREATE TYPE project_nt AS TABLE OF project_ty;
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CREATE TABLE department(  deptno NUMBER(2) PRIMARY KEY,  dname VARCHAR(20) NOT NULL,  projects project_nt) NESTED TABLE projects STORE AS project_nt_tab_temp;
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INSERT INTO department(deptno, dname, projects) VALUES(  1,  'ERP??',  project_nt(    project_ty(1001, 'ERP??', sysdate),    project_ty(1002, 'CRM??', sysdate),    project_ty(1003, 'OA??', sysdate)  ));
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SELECT * FROM department;
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SELECT * FROM TABLE (SELECT projects FROM department WHERE deptno = 1);
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UPDATE TABLE (SELECT projects FROM department WHERE deptno = 1) pro SET VALUE(pro) = project_ty('1001', '?ERP??', TO_DATE('1998-02-12', 'yyyy-mm-dd')) WHERE pro.proid = 1001;
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SELECT * FROM TABLE (SELECT projects FROM department WHERE deptno = 1);