Add row-range query (queryByRow) across C/C++, Python and Java#740
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hongzhi-gao wants to merge 16 commits intoapache:developfrom
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Add row-range query (queryByRow) across C/C++, Python and Java#740hongzhi-gao wants to merge 16 commits intoapache:developfrom
hongzhi-gao wants to merge 16 commits intoapache:developfrom
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Background
TsFile previously only supported time-range queries. Users who want pagination or bulk-read of the first/last N rows had no efficient way to do it without reading the entire dataset first.
What this PR does
Introduces a queryByRow(offset, limit) API across all three language bindings:
C/C++: RowRangeResultSet wrapper that skips the first offset rows then returns at most limit rows. Exposed via TsFileTreeReader::queryByRow and TsFileReader::queryByRow, plus C-wrapper functions tsfile_reader_query_tree_by_row / tsfile_reader_query_table_by_row. limit < 0 means unlimited.
Python: TsFileReaderPy.query_tree_by_row and query_table_by_row Cython bindings that delegate to the C++ layer.
Java: RowRangeResultSet wrapper with the same semantics added to ITsFileTreeReader / ITsFileReader; implemented in TsFileTreeReader and DeviceTableModelReader.
Key design: once limit rows have been returned, next() returns false immediately without loading further chunks/pages, making the stop early efficient.
Tests added
Each binding has dedicated tests covering: limit=0, limit < total, limit > total, limit=-1 (unlimited), offset-only, offset+limit, offset beyond end, data-value correctness, metadata accessibility, and pagination consistency. C also adds C-wrapper smoke tests.