UNION ALL

UNION ALL combines two tables, row by row. Implement UNION ALL by using the SQL panel of Studio Modeler.

Syntax

SELECT columnA [, columnB, ... ]

FROM table1

UNION ALL

SELECT columnA [, columnB, ... ]

FROM table2

Remarks

Multiple column selections can be made, but the number of columns and the column data types should match. All queries in a SQL statement containing the UNION ALL function must have an equal number of expressions in their target lists, as shown in the following example.

Example

SELECT ProductID, ProductName, UnitPrice

FROM /shared/examples/ds_inventory/products products

UNION ALL

SELECT ProductID, ProductName, UnitPrice

FROM /shared/examples/ds_inventory/products products_1

Example (To Contrast with Results of UNION)

Suppose that table T1 has columns C1, C2, and C3, and table T2 has columns Ca, Cb, Cc.

Table T1 has these values.

C1	C2	C3
001	Hello	Goodbye
002	Hola	Adios
003	Aloha	Aloha

Table T2 has these values.

Ca	Cb	Cc
003	Aloha	Aloha
004	Alo	Adieu
007	Ciao	Arrivederci

You execute the following query:

SELECT C1 C2 C3 FROM T1

UNION ALL

SELECT Ci Cii Ciii FROM T2

The results returned are shown in the table below.

001	Hello	Goodbye
002	Hola	Adios
003	Aloha	Aloha
003	Aloha	Aloha
004	Alo	Adieu
007	Ciao	Arrivederci

This result set from UNION ALL contrasts with the output of the UNION function, which omits the repeated value of 003.