ACTION QUERIES (SQL COMMANDS ) STRUCTURED QUERY LANGUAGE

ACTION QUERIES (SQL COMMANDS) DATA DEFINITION LANGUAGE DATA MANIPULATION LANGUAGE TRANSACTION CONTROL LANGUAGE DATA CONTROL LANGUAGE

DATA DEFINITION LANGUAGE (DDL ) CREATE ALTER DROP TRUNCATE

DATA MANIPULATION LANGUAGE (DML ) INSERT UPDATE DELETE

TRANSACTION CONTROL LANGUAGE (TCL) COMMIT ROLLBACK SAVEPOINT

DATA CONTROL LANGUAGE (DCL) GRANT REVOKE

DATA TYPES NUMBER (FLOAT) VARCHAR2 DATE 40 DIGITS +SPACE FOR A DECIMAL AND A SIGN UPTO 4000 BYTES 7 DIGITS

TO CREATE A TABLE CREATE TABLE TABLENAME (ATTRIBUTE1 DATATYPE, ATTRIBUTE2 DATATYPE,....);

TO ALTER A TABLE & ADD A COLUMN ALTER TABLE TABLENAME ADD ATTRIBUTE DATATYPE;

TO VIEW THE TABLE SELECT * FROM TABLENAME ;

TO ALTER A TABLE AND MODIFY DATATYPE Alter table tablename modify attribute datatype; (PROVIDED THERE IS NO VALUE IN THE COLUMN)

TO RENAME A TABLE Rename oldtablename to newtablename;

TO DROP A TABLE Drop table tablename;

TO TRUNCATE A TABLE TRUNCATE TABLE TABLENAME;

To insert values into a table INSERT INTO TABLENAME VALUES(VALUE1,VALUE2, VALUE3....);

TO UPDATE VALUES Update tablename set column1=value1, column2=value2 where columnname=value ;

To delete values from a table Delete from tablename where columnname=value;

TO SAVE CHANGES PERMANENT/ TEMPORARY COMMIT; ROLLBACK; SAVEPOINT;

EXAMPLES FOR COMMIT AND ROLLBACK SELECT * FROM EMP; DELETE FROM EMP; Insert into emp(empno) values(1000);

COMMIT; (CHANGES ARE PERMANENT) Insert into emp(empno) values(4000); DELETE FROM EMP;

ROLLBACK; (CHANGES MADE AFTER THE COMMIT OR DDL WILL GET ERASED )

EXAMPLES OF COMMIT, ROLLBACK AND SAVEPOINT UPDATE EMP SET EMPNO=4000 WHERE EMPNO=5000; SAVEPOINT A; INSERT INTO EMP(EMPNO) VALUES(1000); SAVEPOINT B;

INSERT INTO EMP(ENAME) VALUES(‘JAGAN’); ROLLBACK TO B; (CHANGES MADE AFTER THE ROLLBACK B WILL GET ERASED) ROLLBACK TO A; (CHANGES MADE AFTER THE ROLLBACK A WILL GET ERASED)

TO VIEW ROWS WITH SALARY BETWEEN 2000 & 4000 Select ename, sal from ex16 where sal between 2000 and 4000;

TO VIEW PERSONS WHOSE NAME HAS LETTER “A” Select ename from ex16 where ename like ‘%a%’;

TO VIEW PERSONS WHOSE NAME STARTS WITH LETTER “A” Select ename from ex16 where ename like ‘a%’;

FUNCTIONS AGGREGATE FUNCTIONS

MAX (TO FIND THE MAXIMUM VALUE ON THE SET OF VALUES) Select max(salary) from emp;

MIN (TO FIND THE MINIMUM VALUE ON THE SET OF VALUES) SELECT MIN(SALARY) FROM EMP;

MORE EXAMPLES SELECT ENAME, HIREDATE FROM EMP WHERE ENAME<>’RAMAN’ AND DEPTNO=(SELECT DEPTNO FROM EMP WHERE ENAME=‘ASHOK’;

MORE EXAMPLES SELECT EMPNO, ENAME, SAL FROM EMP WHERE SAL>(SELECT AVG(SAL) FROM EMP) ORDER BY SAL DESC;

MORE EXAMPLES SELECT EMPNO, ENAME FROM EMP WHERE DEPTNO IN (SELECT DEPTNO FROM EMP WHERE ENAME LIKE ‘%T%’);

MORE EXAMPLES SELECT ENAME, DEPTNO, JOB WHERE DEPTNO=(SELECT DEPTNO FROM DEPT WHERE LOC=‘DALLAS’);

MORE EXAMPLES SELECT ENAME, SAL FROM EMP WHERE MGR=(SELECT EMPNO FROM EMP WHERE ENAME=‘KING’);

MORE EXAMPLES SELECT DEPTNO, ENAME, JOB FROM EMP WHERE DEPTNO=(SELECT DEPTNO FROM DEPT WHERE DNAME=‘SALES’);

MORE EXAMPLES SELECT ENAME, HIREDATE FROM EMP WHERE HIREDATE=(SELECT MAX(HIREDATE) FROM EMP;

MORE EXAMPLES SELECT EMPNO, ENAME FROM EMP WHERE DEPTNO IN (SELECT DEPTNO FROM EMP WHERE ENAME LIKE ‘%T%’ AND SAL>(SELECT AVG(SAL) FROM EMP));

MORE EXAMPLES SELECT ENAME, DEPTNO, SAL FROM EMP WHERE (DEPTNO, SAL) IN (SELECT DEPTNO, SAL FROM EMP WHERE COMM IS NOT NULL);

MORE EXAMPLES SELECT ENAME, JOB, SAL FROM EMP WHERE SAL>ANY(SELECT SAL FROM EMP WHERE JOB=‘CLERK’) ORDER BY SAL DESC;