contrib/udf/src/udf_samples/uda_sample.cpp

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// to you under the Apache License, Version 2.0 (the
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//
//   http://www.apache.org/licenses/LICENSE-2.0
//
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#include "udf_sample.h"

namespace doris_udf {

// ---------------------------------------------------------------------------
// This is a sample of implementing a COUNT aggregate function.
// ---------------------------------------------------------------------------
void CountInit(FunctionContext* context, BigIntVal* val) {
    val->is_null = false;
    val->val = 0;
}

void CountUpdate(FunctionContext* context, const IntVal& input, BigIntVal* val) {
    if (input.is_null) return;
    ++val->val;
}

void CountMerge(FunctionContext* context, const BigIntVal& src, BigIntVal* dst) {
    dst->val += src.val;
}

BigIntVal CountFinalize(FunctionContext* context, const BigIntVal& val) {
    return val;
}

}