ChDriver.
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Decodes ClickHouse's "Native" block format — the columns and rows of a query result, once any compression envelope has been stripped away.
This is internal to the driver's decoding pipeline. A block carries its
column names, types, and row data; decode_block/1 turns that into
%{columns: [{name, type}], rows: [[term]]}.
Only a pragmatic subset of ClickHouse's type system is supported — see
ChDriver.Types.Registry for the scalar types and
ChDriver.Protocol.Block.Wrappers for compound types like Array,
Map, and Nullable. If you're adding support for a new ClickHouse
type, ARCHITECTURE.md has the map of which module owns what.
Summary
Functions
Decodes a Native block (everything after the external table name): BlockInfo, column count, row count, and each column's name/type/data.
Decodes a Data or ProfileEvents packet body: the external table name, followed by a Native block.
Functions
Decodes a Native block (everything after the external table name): BlockInfo, column count, row count, and each column's name/type/data.
Returns {:ok, %{columns: [{name, type}], rows: [[term]]}, rest},
{:incomplete, binary}, or {:error, reason}.
@spec decode_data_packet(binary(), ChDriver.Protocol.Block.Compressed.method()) :: {:ok, map(), binary()} | {:incomplete, binary()} | {:error, term()}
Decodes a Data or ProfileEvents packet body: the external table name, followed by a Native block.
compression (:none (default) or :lz4) must match whatever was
negotiated for this query — when :lz4, the block is decompressed
before decoding.
Returns {:ok, %{table_name:, columns:, rows:}, rest},
{:incomplete, binary}, or {:error, reason}.