SQL Join - Statement:

SQL Join - Statement:

          SQL joins are used to gather and manipulate data across several tables based on a relationship between certain columns in these tables.

Note: These tables should have common columns.

For Example:

 The tables Order and Part shown in below,

Order Table:

ORDERDATE	NAME	PARTNUM	REMARKS
15-MAY-1996	TRUE WHEEL	42	PAID
19-MAY-1996	TRUE WHEEL	76	PAID
30-MAY-1996	BIKE SPEC	54	PAID
17-JAN-1996	LE SHOPPE	76	PAID
1-JUN-1996	AAA BIKE	10	PAID

Part Table:

PARTNUM	DESCRIPTION	PRICE
54	PEDALS	54.25
42	SEATS	24.50
46	TIRES	15.25
23	MOUNTAIN BIKE	350.45
76	ROAD BIKE	530.00
10	TANDEM	1200.00

Now join PART and ORDERS:

SELECT O.ORDERDATE, O.NAME, O.PARTNUM, P.PARTNUM, P.DESCRIPTION

FROM ORDERS O, PART P WHERE O.PARTNUM = P.PARTNUM

The Result Set is,

ORDERDATE	NAME	PARTNUM	PARTNUM	DESCRIPTION
15-MAY-1996	TRUE WHEEL	42	42	SEATS
30-MAY-1996	BIKE SPEC	54	54	PEDALS
1-JUN-1996	AAA BIKE	10	10	TANDEM

[Note that PARTNUM fields that are common to both tables]