Retain result type after UNION as base type in T-SQL (#487) #503
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…ostgresql#487) Description ----------- When a base type such as `money` is UNIONed with another integer type, the result type will be `fixeddecimal` instead of `money`, which is inconsistent with SQL Server's behaviour. And could also cause some characters not displaying well. Analysis -------- The root cause of the issue is Postgres will consider the base type of domain type as the result type. In Babelfish, `money` is implemented as a domain type of `fixeddecimal`. Actually, `money` is a base type in T-SQL, thus Babelfish should retain `money` type after UNION. Fix --- After a final type has determined by the optimizer, check if it's a base type in T-SQL. If it is, try to use the domain type as result type if the domain type has higher precision than other types. Task: BABEL-5242 Signed-off-by: Bo Li <[email protected]>
shardgupta
approved these changes
Dec 19, 2024
shardgupta
merged commit bdb8416
into
babelfish-for-postgresql:BABEL_3_X_DEV__PG_15_X
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Description
When a base type such as
moneyis UNIONed with another integer type, the result type will befixeddecimalinstead ofmoney, which is inconsistent with SQL Server's behaviour. And could also cause some characters not displaying well.Analysis
The root cause of the issue is Postgres will consider the base type of domain type as the result type. In Babelfish,
moneyis implemented as a domain type offixeddecimal. Actually,moneyis a base type in T-SQL, thus Babelfish should retainmoneytype after UNION.Fix
After a final type has determined by the optimizer, check if it's a base type in T-SQL. If it is, try to use the domain type as result type if the domain type has higher precision than other types.
Task: BABEL-5242
Cherry-picked from https://github.com/amazon-aurora/postgresql_modified_for_babelfish/pull/new/babel_5242_dev15
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