Not able to transform two or more complex Select clauses at a time
Some parts in the output code are omitted for clarity reasons.
Severity
Medium
Description
SnowConvert is not able to transform two or more complex SELECT clauses, as it is necessary to map them to a CTE or composite FROM clause, which causes the mapped code to not compile or enter into a logical cycle.
What do we consider a SELECT complex clause?
Those that required to be mapped to a CTE or composite FROM clause such as NORMALIZE, EXPAND ON, or RESET WHEN.
Example Code
Input Code:
IN -> Teradata_01.sql
SELECT
NORMALIZE emp_id,
duration,
dept_id,
balance,
(
ROW_NUMBER() OVER (
PARTITION BY emp_id
ORDER BY
dept_id RESET WHEN balance <= SUM(balance) OVER (
PARTITION BY emp_id
ORDER BY dept_id
ROWS BETWEEN 1 PRECEDING AND 1 PRECEDING
)
) -1
) AS balance_increase
FROM project
EXPAND ON duration AS bg BY ANCHOR ANCHOR_SECOND
ORDER BY 1, 2;
Output Code
OUT -> Teradata_01.sql
// SnowConvert Helpers Code section is omitted.
SELECT
!!!RESOLVE EWI!!! /*** SSC-EWI-TD0083 - NOT ABLE TO TRANSFORM TWO OR MORE COMPLEX SELECT CLAUSES AT A TIME ***/!!!
NORMALIZE emp_id,
duration,
dept_id,
balance,
(
ROW_NUMBER() OVER (
PARTITION BY
emp_id, new_dynamic_part
ORDER BY
dept_id
) -1
) AS balance_increase
FROM
(
SELECT
emp_id,
duration,
dept_id,
balance,
previous_value,
SUM(dynamic_part) OVER (
PARTITION BY emp_id
ORDER BY dept_id
ROWS BETWEEN UNBOUNDED PRECEDING AND CURRENT ROW
) AS new_dynamic_part
FROM
(
SELECT
emp_id,
duration,
dept_id,
balance,
SUM(balance) OVER (
PARTITION BY emp_id
ORDER BY dept_id
ROWS BETWEEN 1 PRECEDING AND 1 PRECEDING
) AS previous_value,
(CASE
WHEN balance <= previous_value
THEN 1
ELSE 0
END) AS dynamic_part
FROM
project
)
)
!!!RESOLVE EWI!!! /*** SSC-EWI-TD0083 - NOT ABLE TO TRANSFORM TWO OR MORE COMPLEX SELECT CLAUSES AT A TIME ***/!!!
EXPAND ON duration AS bg BY ANCHOR ANCHOR_SECOND
ORDER BY 1, 2;
