ClickHouse

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#include <Columns/ColumnConst.h>
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#include <Columns/ColumnString.h>
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#include <DataTypes/DataTypeString.h>
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#include <DataTypes/DataTypesNumber.h>
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#include <Functions/FunctionFactory.h>
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#include <Functions/FunctionHelpers.h>
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#include <Functions/IFunction.h>
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#include <Common/logger_useful.h>
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namespace DB
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{
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namespace ErrorCodes
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{
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    extern const int ILLEGAL_TYPE_OF_ARGUMENT;
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}
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namespace
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{
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    class FunctionLogTrace : public IFunction
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    {
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    public:
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        static constexpr auto name = "logTrace";
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        static FunctionPtr create(ContextPtr) { return std::make_shared<FunctionLogTrace>(); }
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        String getName() const override { return name; }
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        size_t getNumberOfArguments() const override { return 1; }
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        bool isSuitableForShortCircuitArgumentsExecution(const DataTypesWithConstInfo & /*arguments*/) const override { return false; }
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        DataTypePtr getReturnTypeImpl(const DataTypes & arguments) const override
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        {
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            if (!isString(arguments[0]))
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                throw Exception(ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT, "Illegal type {} of argument of function {}",
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                    arguments[0]->getName(), getName());
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            return std::make_shared<DataTypeUInt8>();
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        }
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        ColumnPtr executeImpl(const ColumnsWithTypeAndName & arguments, const DataTypePtr &, size_t input_rows_count) const override
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        {
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            String message;
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            if (const ColumnConst * col = checkAndGetColumnConst<ColumnString>(arguments[0].column.get()))
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                message = col->getDataAt(0).data;
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            else
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                throw Exception(ErrorCodes::ILLEGAL_TYPE_OF_ARGUMENT, "First argument for function {} must be Constant string",
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                    getName());
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            static auto log = getLogger("FunctionLogTrace");
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            LOG_TRACE(log, fmt::runtime(message));
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            return DataTypeUInt8().createColumnConst(input_rows_count, 0);
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        }
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    };
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}
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REGISTER_FUNCTION(LogTrace)
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{
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    factory.registerFunction<FunctionLogTrace>();
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}
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}
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