Oracle instances, specifically using

Use of Oracle Keywords

Use Insert to add data: INSERT into table name VALUES (add corresponding number); COMMIT;

INSERT into P_emp

VALUES (' TOM2 ', ' clerk ', 7902, Sysdate,, NULL, 30);

COMMIT;

Try delete Delete a data: Delete table name WHERE condition; COMMIT;

DELETE p_emp e WHERE e.empno=1;

COMMIT;

Use Update to modify data: Update table name SET Modify the content WHERE condition; COMMIT;

UPDATE p_emp e SET e.ename= ' TOM3 ' WHERE e.empno=2;

COMMIT;

In keyword, query for data that conforms to the in condition. Example: Query employee information for payroll 800,3000,5000

SELECT * from P_emp e WHERE e.sal in (800, 3000, 5000);

Like keyword, fuzzy query,% denotes any character, _ represents a single character. Example: Query the employee's information that starts with T

SELECT * from P_emp e WHERE e.ename like ' t% '

Order BY, sort by column name or index

SELECT * from P_emp e ORDER by e.job desc, e.sal desc

SELECT * from P_emp e ORDER by 3, 6

Group BY is grouped by a few columns

SELECT e.job from P_emp e GROUP by E.job have COUNT (*) > 2

Using the Sum,avg,mod,count function

SELECT P.toma,p.ptype,sum (P.lastcou) from product P GROUP by ROLLUP (P.toma,p.type)

Use of case when Then/decode

Case * When condition then display content

DECODE (*, ' condition ', ' show content ')

SELECT T.ename,

Case T.sex If 1 then ' Male ' when 0 Then ' women ' ELSE ' KK ' END

From P_emp T

SELECT t.ename Name,

case if T.sex = 1 Then ' male ' when t.sex = 0 Then ' women ' ELSE ' KK '

END Sex

From P_emp T

Distinct removing duplicates

SELECT DISTINCT t.job from P_emp t

Between A and b between A and B

SELECT * from P_emp t WHERE t.sal between and 3000

Oracle instances, specifically using