snowflake object_construct is converted to duckdb map with values of single type

[tekumara]

In Snowflake, OBJECT_CONSTRUCT can be used to construct an object from the given key-value pairs. Keys must be strings, but values can be any type and can differ from each other.

When converting OBJECT_CONSTRUCT to duckdb, it ends up as a map. Maps must have a single type for all keys, and a single type for all values.

eg:

sqlglot.parse_one("SELECT OBJECT_CONSTRUCT('a',1,'b','BBBB', 'c',null)", read="snowflake").sql(dialect="duckdb")

"SELECT MAP(LIST_VALUE('a', 'b', 'c'), LIST_VALUE(1, 'BBBB', NULL))"

Because the map/list must be of the same type, in this example the integer 1 becomes the string "1" when the expression is executed in duckdb:

D SELECT to_json(MAP(LIST_VALUE('a', 'b', 'c'), LIST_VALUE(1, 'BBBB', NULL)));
┌──────────────────────────────────────────────────────────────────────┐
│ to_json(map(list_value('a', 'b', 'c'), list_value(1, 'BBBB', NULL))) │
│                                 json                                 │
├──────────────────────────────────────────────────────────────────────┤
│ {"a":"1","b":"BBBB","c":null}                                        │
└──────────────────────────────────────────────────────────────────────┘

NB: to_json is used here to show that the value for thea key is a string.

[georgesittas]

Do you know if there's an equivalent concept in DuckDB to improve the transpilation? For example, would DuckDB's structs be more suitable here, or is there a difference in semantics?

[pkit]

Yup, struct should behave as needed, I think. As struct is the only type (besides list) that can contain other structs.
And in Snowflake OBJECT can contain other objects too.

[georgesittas]

Ok, thanks for confirming. I'll look into this a bit closer and try to fix it on Monday.