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MSCEWI4030

Warning while OUTER JOIN equivalence is checked.

Severity

Low

Description

The current equivalency used to represent the OUTER APPLY in Snowflake is the LEFT OUTER JOIN, but this target statement must be checked and confirm if this transformation rule is accurate.

Code Example

Input Code:

SELECT TOPS.* from Customers as C
OUTER APPLY (SELECT TOP 1 O.code
FROM Orders AS O
WHERE O.customer_id = C.customer_id
ORDER BY O.code) AS TOPS;

Output Code:

SELECT TOPS.* from Customers as C
LEFT OUTER JOIN (SELECT TOP 1 O.code
FROM Orders AS O
WHERE O.customer_id = C.customer_id
ORDER BY O.code) AS TOPS /*** MSC-WARNING - MSCEWI4030 - Equivalence from OUTER APPLY to LEFT OUTER JOIN must be checked. ***/;

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