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// Copyright 2012 Cloudera Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef SAMPLES_UDF_H
#define SAMPLES_UDF_H
#include <impala_udf/udf.h>
using namespace impala_udf;
// Usage: > create function add(int, int) returns int
// location '/user/cloudera/libudfsample.so' SYMBOL='AddUdf';
// > select add(1, 2);
IntVal AddUdf(FunctionContext* context, const IntVal& arg1, const IntVal& arg2);
// Returns true if x is approximately equal to y.
// Usage: > create function fuzzy_equals(double, double) returns boolean
// location '/user/cloudera/libudfsample.so' SYMBOL='FuzzyEquals';
// > select fuzzy_equals(1, 1.00000001);
BooleanVal FuzzyEquals(FunctionContext* context, const DoubleVal& x, const DoubleVal& y);
// Perform tests, calculations, and transformations
// on a string value, using the set of letters 'aeiou'.
// Usage: > create function hasvowels(string) returns boolean
// location '/user/cloudera/libudfsample.so' SYMBOL='HasVowels';
// > select hasvowels('banana');
// > select hasvowels('grr hm shhh');
// > select hasvowels(c1) from t1;
BooleanVal HasVowels(FunctionContext* context, const StringVal& input);
// Usage: > create function countvowels(string) returns int
// location '/user/cloudera/libudfsample.so' SYMBOL='CountVowels';
// > select countvowels('abracadabra hocus pocus');
// > select countvowels(c1) from t1;
IntVal CountVowels(FunctionContext* context, const StringVal& arg1);
// Usage: > create function stripvowels(string) returns string
// location '/user/cloudera/libudfsample.so' SYMBOL='StripVowels';
// > select stripvowels('colour color');
// > select stripvowels(c1) from t1;
StringVal StripVowels(FunctionContext* context, const StringVal& arg1);
// If 'val' is constant, returns 'val', otherwise returns null. This is a simple toy UDF
// demonstrating how to use prepare and close functions to maintain shared state.
// Requires Impala 1.3 or higher.
// Usage: > create function constantarg(int) returns int
// location '/user/cloudera/libudfsample.so' symbol='ReturnConstantArg'
// prepare_fn='ReturnConstantArgPrepare' close_fn='ReturnConstantArgClose';
// > select constantarg(1 + 1);
// > select constantarg(c1) from t1 limit 1;
IntVal ReturnConstantArg(FunctionContext* context, const IntVal& val);
void ReturnConstantArgPrepare(
FunctionContext* context, FunctionContext::FunctionStateScope scope);
void ReturnConstantArgClose(
FunctionContext* context, FunctionContext::FunctionStateScope scope);
#endif
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