apache
[feature](function) support type template in SQL function
Proposed changes
Issue Number: close #xxx
Problem summary
Currently, for ARRAY and MAP functions, sub item datatype need to be enumerated in FE function registration. It's tedious and hard to maintain for adding new datatypes.
# map element extract functions
[['element_at', '%element_extract%'], 'DECIMAL64', ['ARRAY_DECIMAL64', 'BIGINT'], 'ALWAYS_NULLABLE'],
[['element_at', '%element_extract%'], 'DECIMAL128', ['ARRAY_DECIMAL128', 'BIGINT'], 'ALWAYS_NULLABLE'],
[['element_at', '%element_extract%'], 'VARCHAR', ['ARRAY_VARCHAR', 'BIGINT'], 'ALWAYS_NULLABLE'],
[['element_at', '%element_extract%'], 'STRING', ['ARRAY_STRING', 'BIGINT'], 'ALWAYS_NULLABLE'],
and many more ...
# map element extract functions
[['element_at', '%element_extract%'], 'INT', ['MAP_STRING_INT', 'STRING'], 'ALWAYS_NULLABLE'],
[['element_at', '%element_extract%'], 'STRING', ['MAP_INT_STRING', 'INT'], 'ALWAYS_NULLABLE'],
and many more ...
A new way just like c++ template is proposed in this PR. The previous functions can be defined much simpler using template function. # map element extract template function [['element_at', '%element_extract%'], 'E', ['ARRAY<E>', 'BIGINT'], 'ALWAYS_NULLABLE', ['E']],
# map element extract template function
[['element_at', '%element_extract%'], 'V', ['MAP<K, V>', 'K'], 'ALWAYS_NULLABLE', ['K', 'V']],
BTW, the plain type function is not affected and the legacy ARRAY_X MAP_K_V is still supported for compatability.
Checklist(Required)
- [ ] Does it affect the original behavior
- [ ] Has unit tests been added
- [ ] Has document been added or modified
- [ ] Does it need to update dependencies
- [ ] Is this PR support rollback (If NO, please explain WHY)
Further comments
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PR approved by at least one committer and no changes requested.
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PR approved by at least one committer and no changes requested.