UNION_ALL_PULLBACK

Description

The UNION_ALL_PULLBACK function returns the column corresponding to the index requested from the UNION_ALL table.

SYNTAX

 UNION_ALL_PULLBACK ( expression, index )

NULL handling

NULL values are preserved.

Limitations

The current limitations documented in Engine Limitations also hold for the result of UNION_ALL_PULLBACK. This means that the hard upper limit of rows for the result column of UNION_ALL_PULLBACK is 2.1 billion rows, and the recommended limit of rows is 800 million rows.

Examples

[1]

Query

Column1

         UNION_ALL_PULLBACK ( UNION_ALL ( "caseTable"."orderid" , "activityTable"."activity" ) , 2 )

Input

Output

City

city : string	size : int
'Frankfurt'	3500000
'Boston'	600000
'Lyon'	2200000
'Seattle'	640000

Country

country : string	capitol : string
'DE'	'Berlin'
'US'	'Washington'
'FR'	'Paris'

OrderPos

orderId : string	pos : int	country : string	city : string
'001'	1	'DE'	'Frankfurt'
'001'	2	'US'	'Boston'
'001'	3	'FR'	'Lyon'
'002'	1	'US'	'Seattle'

activityTable

activity : string	caseId : int
'A'	1
'B'	1
'C'	2

caseTable

caseId : int	orderId : string
1	'001'
2	'002'

Foreign Keys

caseTable.caseId	activityTable.caseId
caseTable.orderId	OrderPos.orderId
OrderPos.country	Country.country
OrderPos.city	City.city

Result

Column1 : string
'A'
'B'
'C'

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