be/src/exprs/conditional-functions.h

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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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#ifndef IMPALA_EXPRS_CONDITIONAL_FUNCTIONS_H
#define IMPALA_EXPRS_CONDITIONAL_FUNCTIONS_H

#include <stdint.h>

#include "exprs/expr.h"
#include "udf/udf.h"

using namespace impala_udf;

namespace impala {

class TupleRow;

/// Conditional functions that can be expressed as UDFs
class ConditionalFunctions {
 public:
  static TinyIntVal NullIfZero(FunctionContext* context, const TinyIntVal& val);
  static SmallIntVal NullIfZero(FunctionContext* context, const SmallIntVal& val);
  static IntVal NullIfZero(FunctionContext* context, const IntVal& val);
  static BigIntVal NullIfZero(FunctionContext* context, const BigIntVal& val);
  static FloatVal NullIfZero(FunctionContext* context, const FloatVal& val);
  static DoubleVal NullIfZero(FunctionContext* context, const DoubleVal& val);
  static DecimalVal NullIfZero(FunctionContext* context, const DecimalVal& val);

  static TinyIntVal ZeroIfNull(FunctionContext* context, const TinyIntVal& val);
  static SmallIntVal ZeroIfNull(FunctionContext* context, const SmallIntVal& val);
  static IntVal ZeroIfNull(FunctionContext* context, const IntVal& val);
  static BigIntVal ZeroIfNull(FunctionContext* context, const BigIntVal& val);
  static FloatVal ZeroIfNull(FunctionContext* context, const FloatVal& val);
  static DoubleVal ZeroIfNull(FunctionContext* context, const DoubleVal& val);
  static DecimalVal ZeroIfNull(FunctionContext* context, const DecimalVal& val);

  /// Functions IsFalse and IsTrue return false when the input is NULL.
  /// Functions IsNotFalse and IsNotTrue return true when the input is NULL.
  static BooleanVal IsFalse(FunctionContext* ctx, const BooleanVal& val);
  static BooleanVal IsNotFalse(FunctionContext* ctx, const BooleanVal& val);
  static BooleanVal IsTrue(FunctionContext* ctx, const BooleanVal& val);
  static BooleanVal IsNotTrue(FunctionContext* ctx, const BooleanVal& val);
};

/// The following conditional functions require separate Expr classes to take advantage of
/// short circuiting

class IsNullExpr : public Expr {
 public:
  virtual BooleanVal GetBooleanVal(ExprContext* context, const TupleRow* row);
  virtual TinyIntVal GetTinyIntVal(ExprContext* context, const TupleRow* row);
  virtual SmallIntVal GetSmallIntVal(ExprContext* context, const TupleRow* row);
  virtual IntVal GetIntVal(ExprContext* context, const TupleRow* row);
  virtual BigIntVal GetBigIntVal(ExprContext* context, const TupleRow* row);
  virtual FloatVal GetFloatVal(ExprContext* context, const TupleRow* row);
  virtual DoubleVal GetDoubleVal(ExprContext* context, const TupleRow* row);
  virtual StringVal GetStringVal(ExprContext* context, const TupleRow* row);
  virtual TimestampVal GetTimestampVal(ExprContext* context, const TupleRow* row);
  virtual DecimalVal GetDecimalVal(ExprContext* context, const TupleRow* row);

  virtual Status GetCodegendComputeFn(LlvmCodeGen* codegen, llvm::Function** fn);
  virtual std::string DebugString() const { return Expr::DebugString("IsNullExpr"); }

 protected:
  friend class Expr;
  IsNullExpr(const TExprNode& node) : Expr(node) { }
};

class NullIfExpr : public Expr {
 public:
  virtual BooleanVal GetBooleanVal(ExprContext* context, const TupleRow* row);
  virtual TinyIntVal GetTinyIntVal(ExprContext* context, const TupleRow* row);
  virtual SmallIntVal GetSmallIntVal(ExprContext* context, const TupleRow* row);
  virtual IntVal GetIntVal(ExprContext* context, const TupleRow* row);
  virtual BigIntVal GetBigIntVal(ExprContext* context, const TupleRow* row);
  virtual FloatVal GetFloatVal(ExprContext* context, const TupleRow* row);
  virtual DoubleVal GetDoubleVal(ExprContext* context, const TupleRow* row);
  virtual StringVal GetStringVal(ExprContext* context, const TupleRow* row);
  virtual TimestampVal GetTimestampVal(ExprContext* context, const TupleRow* row);
  virtual DecimalVal GetDecimalVal(ExprContext* context, const TupleRow* row);

  virtual Status GetCodegendComputeFn(LlvmCodeGen* codegen, llvm::Function** fn);
  virtual std::string DebugString() const { return Expr::DebugString("NullIfExpr"); }

 protected:
  friend class Expr;
  NullIfExpr(const TExprNode& node) : Expr(node) { }
};

class IfExpr : public Expr {
 public:
  virtual BooleanVal GetBooleanVal(ExprContext* context, const TupleRow* row);
  virtual TinyIntVal GetTinyIntVal(ExprContext* context, const TupleRow* row);
  virtual SmallIntVal GetSmallIntVal(ExprContext* context, const TupleRow* row);
  virtual IntVal GetIntVal(ExprContext* context, const TupleRow* row);
  virtual BigIntVal GetBigIntVal(ExprContext* context, const TupleRow* row);
  virtual FloatVal GetFloatVal(ExprContext* context, const TupleRow* row);
  virtual DoubleVal GetDoubleVal(ExprContext* context, const TupleRow* row);
  virtual StringVal GetStringVal(ExprContext* context, const TupleRow* row);
  virtual TimestampVal GetTimestampVal(ExprContext* context, const TupleRow* row);
  virtual DecimalVal GetDecimalVal(ExprContext* context, const TupleRow* row);

  virtual Status GetCodegendComputeFn(LlvmCodeGen* codegen, llvm::Function** fn);
  virtual std::string DebugString() const { return Expr::DebugString("IfExpr"); }

 protected:
  friend class Expr;
  IfExpr(const TExprNode& node) : Expr(node) { }
};

class CoalesceExpr : public Expr {
 public:
  virtual BooleanVal GetBooleanVal(ExprContext* context, const TupleRow* row);
  virtual TinyIntVal GetTinyIntVal(ExprContext* context, const TupleRow* row);
  virtual SmallIntVal GetSmallIntVal(ExprContext* context, const TupleRow* row);
  virtual IntVal GetIntVal(ExprContext* context, const TupleRow* row);
  virtual BigIntVal GetBigIntVal(ExprContext* context, const TupleRow* row);
  virtual FloatVal GetFloatVal(ExprContext* context, const TupleRow* row);
  virtual DoubleVal GetDoubleVal(ExprContext* context, const TupleRow* row);
  virtual StringVal GetStringVal(ExprContext* context, const TupleRow* row);
  virtual TimestampVal GetTimestampVal(ExprContext* context, const TupleRow* row);
  virtual DecimalVal GetDecimalVal(ExprContext* context, const TupleRow* row);

  virtual std::string DebugString() const { return Expr::DebugString("CoalesceExpr"); }

 protected:
  friend class Expr;
  CoalesceExpr(const TExprNode& node) : Expr(node) { }
  virtual Status GetCodegendComputeFn(LlvmCodeGen* codegen, llvm::Function** fn);
};

}

#endif