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The mappings already work for the HTTP engine, although its inserts were limited to `float8`, now fixed to use proper numeric formatting. Add the mappings for the binary engine. Use strings to convert between the Postgres and ClickHouse formats to as to avoid differences in their implementations: ClickHouse stores data as `Int32`, `Int64`, or `Int128`, while Postgres...well, I have no idea what the internals are, but using the `numeric_in` and `numeric_out` functions avoid all issues. Conversion from `Decimal` values returned from ClickHouse requires converting its internal `Int128` into a string. The clickhouse-cpp library doesn't provide this functionality, [yet], so implement it here. Unfortunately, this approach doesn't work with clickhouse-cpp compiled into a dynamic library, presumably because it doesn't also compile and install the `absl` dynamic library. So make the build static by default on all platforms for now. Add a test that covers both the HTTP and binary engines. [yet]: ClickHouse/clickhouse-cpp#451
serprex
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The mappings already work for the HTTP engine, although its inserts were limited to
float8, now fixed to use proper numeric formatting.Add the mappings for the binary engine. Use strings to convert between the Postgres and ClickHouse formats to as to avoid differences in their implementations: ClickHouse stores data as
Int32,Int64, orInt128, while Postgres...well, I have no idea what the internals are, but using thenumeric_inandnumeric_outfunctions avoid all issues.Conversion from
Decimalvalues returned from ClickHouse requires converting its internalInt128into a string. The clickhouse-cpp library doesn't provide this functionality, yet, so implement it here.Unfortunately, this approach doesn't work with clickhouse-cpp compiled into a dynamic library, presumably because it doesn't also compile and install the
absldynamic library. So make the build static by default on all platforms for now.Add a test that covers both the HTTP and binary engines.