ClickHouse/src/Functions/visitParamExtractString.cpp
2021-04-01 23:07:01 +03:00

33 lines
1.1 KiB
C++

#include <Functions/FunctionFactory.h>
#include <Functions/FunctionsVisitParam.h>
#include <Functions/FunctionsStringSearchToString.h>
namespace DB
{
struct ExtractString
{
static void extract(const UInt8 * pos, const UInt8 * end, ColumnString::Chars & res_data)
{
size_t old_size = res_data.size();
ReadBufferFromMemory in(pos, end - pos);
if (!tryReadJSONStringInto(res_data, in))
res_data.resize(old_size);
}
};
struct NameVisitParamExtractString { static constexpr auto name = "visitParamExtractString"; };
using FunctionVisitParamExtractString = FunctionsStringSearchToString<ExtractParamToStringImpl<ExtractString>, NameVisitParamExtractString>;
struct NameSimpleJSONExtractString { static constexpr auto name = "simpleJSONExtractString"; };
using FunctionSimpleJSONExtractString = FunctionsStringSearchToString<ExtractParamToStringImpl<ExtractString>, NameSimpleJSONExtractString>;
void registerFunctionVisitParamExtractString(FunctionFactory & factory)
{
factory.registerFunction<FunctionVisitParamExtractString>();
factory.registerFunction<FunctionSimpleJSONExtractString>();
}
}