Appender: support composite/nested lists and maps#399
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This PR adds support for appending to `MAP` and composite `LIST` columns, for example `LIST` of `STRUCT`s, `LIST` of `ARRAY`s or nested `LIST`s. It should cover virtually any table schema with composite fields, with the notable exception of `ARRAY`s with more than 2 dimensions (like `INT[2][3][4]`) - only 2D `ARRAY`s are supported. Higher dimensions could be possible, but the interface for them appeared to be tough to generalize. `LIST`s of `ARRAY`s can be used instead, like `INT[2][3][]`. `LIST`s can be specified as a `Collection` or `Iterator` (with `count`) of objects. `MAP`s are specified as `java.util.Map` instances. `STRUCT` inside a `LIST` can be specified either as `java.utils.LinkedHashMap` (keys are ignored) or as a `Collection` of values for `STRUCT` fields. `UNION` inside a `LIST` can be specified as an instance of `java.util.AbstractMap.SimpleEntry`, where a `key` is used as a tag to choose which `UNION` field to append to. If some required input cases are missed - please raise an issue. Testing: new tests added to cover various combinations of nesting.
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This is a backport of the PR duckdb#399 to `v1.4-andium` stable branch. This PR adds support for appending to `MAP` and composite `LIST` columns, for example `LIST` of `STRUCT`s, `LIST` of `ARRAY`s or nested `LIST`s. It should cover virtually any table schema with composite fields, with the notable exception of `ARRAY`s with more than 2 dimensions (like `INT[2][3][4]`) - only 2D `ARRAY`s are supported. Higher dimensions could be possible, but the interface for them appeared to be tough to generalize. `LIST`s of `ARRAY`s can be used instead, like `INT[2][3][]`. `LIST`s can be specified as a `Collection` or `Iterator` (with `count`) of objects. `MAP`s are specified as `java.util.Map` instances. `STRUCT` inside a `LIST` can be specified either as `java.utils.LinkedHashMap` (keys are ignored) or as a `Collection` of values for `STRUCT` fields. `UNION` inside a `LIST` can be specified as an instance of `java.util.AbstractMap.SimpleEntry`, where a `key` is used as a tag to choose which `UNION` field to append to. If some required input cases are missed - please raise an issue. Testing: new tests added to cover various combinations of nesting.
staticlibs
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This is a backport of the PR #399 to `v1.4-andium` stable branch. This PR adds support for appending to `MAP` and composite `LIST` columns, for example `LIST` of `STRUCT`s, `LIST` of `ARRAY`s or nested `LIST`s. It should cover virtually any table schema with composite fields, with the notable exception of `ARRAY`s with more than 2 dimensions (like `INT[2][3][4]`) - only 2D `ARRAY`s are supported. Higher dimensions could be possible, but the interface for them appeared to be tough to generalize. `LIST`s of `ARRAY`s can be used instead, like `INT[2][3][]`. `LIST`s can be specified as a `Collection` or `Iterator` (with `count`) of objects. `MAP`s are specified as `java.util.Map` instances. `STRUCT` inside a `LIST` can be specified either as `java.utils.LinkedHashMap` (keys are ignored) or as a `Collection` of values for `STRUCT` fields. `UNION` inside a `LIST` can be specified as an instance of `java.util.AbstractMap.SimpleEntry`, where a `key` is used as a tag to choose which `UNION` field to append to. If some required input cases are missed - please raise an issue. Testing: new tests added to cover various combinations of nesting.
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This PR adds support for appending to
MAPand compositeLISTcolumns, for exampleLISTofSTRUCTs,LISTofARRAYs or nestedLISTs.It should cover virtually any table schema with composite fields, with the notable exception of
ARRAYs with more than 2 dimensions (likeINT[2][3][4]) - only 2DARRAYs are supported. Higher dimensions could be possible, but the interface for them appeared to be tough to generalize.LISTs ofARRAYs can be used instead, likeINT[2][3][].Non-primitive
LISTs can be specified as aCollectionorIterator(withcount) of objects.MAPs can be specified asjava.util.Mapinstances.STRUCTinside aLISTcan be specified either asjava.utils.LinkedHashMap(keys are ignored) or as aCollectionofvalues for
STRUCTfields.UNIONinside aLISTcan be specified as an instance ofjava.util.AbstractMap.SimpleEntry, where akeyis used as a tag to choose whichUNIONfield to append to.If some required input cases are missing - please raise an issue.
Testing: new tests added to cover various combinations of nesting.
Fixes: #307, #344