A row of complex type may be stored across two(or more) pages, and the parameter `align_rows` indicates that whether the reader should read the remaining value of the last row in previous page.
`ParquetReader` confuses logical/physical/slot id of columns. If only reading the scalar types, there's nothing wrong, but when reading complex types, `RowGroup` and `PageIndex` will get wrong statistics. Therefore, if the query contains complex types and pushed-down predicates, the probability of the result set is incorrect.
Now we can not support nested type array/map
so this pr aim to:
1. add format option for string convert defined datatype to keep with origin from_string
2. support array map can nested array and map
Iceberg has its own metadata information, which includes count statistics for table data. If the table does not contain equli'ty delete, we can get the count data of the current table directly from the count statistics.
[Fix](orc-reader) Fix filling partition or missing column used incorrect row count.
`_row_reader->nextBatch` returns number of read rows. When orc lazy materialization is turned on, the number of read rows includes filtered rows, so caller must look at `numElements` in the row batch to determine how
many rows were not filtered which will to fill to the block.
In this case, filling partition or missing column used incorrect row count which will cause be crash by `filter.size() != offsets.size()` in filter column step.
When orc lazy materialization is turned off, add `_convert_dict_cols_to_string_cols(block, nullptr)` if `(block->rows() == 0)`.
This issue is introduced by #22765, if #22765 is picked to 2.0, then also need to pick this PR.
When shuffle type is BUCKET_SHFFULE_HASH_PARTITIONED, since data of multi buckets maybe sent to the same channel, send eos too early may cause data lost.
before the parquet write export decimal as byte-binary,
but can't be import those fied to Hive.
Now, change to export decimal as fixed-len-byte-array in order to import hive directly.
## Proposed changes
Refactor thoughts: close#22383
Descriptions about `enclose` and `escape`: #22385
## Further comments
2023-08-09:
It's a pity that experiment shows that the original way for parsing plain CSV is faster. Therefor, the refactor is only applied on enclose related code. The plain CSV parser use the original logic.
Fallback of performance is unavoidable anyway. From the `CSV reader`'s perspective, the real weak point may be the write column behavior, proved by the flame graph.
Trimming escape will be enable after fix: #22411 is merged
Cases should be discussed:
1. When an incomplete enclose appears in the beginning of a large scale data, the line delimiter will be unreachable till the EOF, will the buffer become extremely large?
2. What if an infinite line occurs in the case? Essentially, `1.` is equivalent to this.
Only support stream load as trial in this PR, avoid too many unrelated changes. Docs will be added when `enclose` and `escape` is available for all kinds of load.