PostgreSQL 聚合函数的实现教程

本篇内容主要讲解“PostgreSQL 聚合函数的实现教程”，感兴趣的朋友不妨来看看。本文介绍的方法操作简单快捷，实用性强。下面就让小编来带大家学习“PostgreSQL 聚合函数的实现教程”吧!

一、数据结构

AggState
聚合函数执行时状态结构体,内含AggStatePerAgg等结构体

//在nodeAgg.c中私有的结构体
typedef struct AggStatePerAggData *AggStatePerAgg;
typedef struct AggStatePerTransData *AggStatePerTrans;
typedef struct AggStatePerGroupData *AggStatePerGroup;
typedef struct AggStatePerPhaseData *AggStatePerPhase;
typedef struct AggStatePerHashData *AggStatePerHash;
typedef struct AggState
{
    //第一个字段是NodeTag(继承自ScanState)
    ScanState    ss;                
    //targetlist和quals中所有的Aggref
    List       *aggs;            
    //链表的大小(可以为0)
    int            numaggs;        
    //pertrans条目大小
    int            numtrans;        
    //Agg策略模式
    AggStrategy aggstrategy;    
    //agg-splitting模式,参见nodes.h
    AggSplit    aggsplit;        
    //指向当前步骤数据的指针
    AggStatePerPhase phase;        
    //步骤数(包括0)
    int            numphases;        
    //当前步骤
    int            current_phase;    
    //per-Aggref信息
    AggStatePerAgg peragg;        
    //per-Trans状态信息
    AggStatePerTrans pertrans;    
    //长生命周期数据的ExprContexts(hashtable)
    ExprContext *hashcontext;    
    ////长生命周期数据的ExprContexts(每一个GS使用)
    ExprContext **aggcontexts;    
    //输入表达式的ExprContext
    ExprContext *tmpcontext;    
#define FIELDNO_AGGSTATE_CURAGGCONTEXT 14
    //当前活跃的aggcontext
    ExprContext *curaggcontext; 
    //当前活跃的aggregate(如存在)
    AggStatePerAgg curperagg;    
#define FIELDNO_AGGSTATE_CURPERTRANS 16
    //当前活跃的trans state
    AggStatePerTrans curpertrans;    
    //输入结束?
    bool        input_done;        
    //Agg扫描结束?
    bool        agg_done;        
    //最后一个grouping set
    int            projected_set;    
#define FIELDNO_AGGSTATE_CURRENT_SET 20
    //将要解析的当前grouping set
    int            current_set;    
    //当前投影操作的分组列
    Bitmapset  *grouped_cols;    
    //倒序的分组列链表
    List       *all_grouped_cols;    
    
    //-------- 下面的列用于grouping set步骤数据
    //所有步骤中最大的sets大小
    int            maxsets;        
    //所有步骤的数组
    AggStatePerPhase phases;    
    //对于phases > 1,已排序的输入信息
    Tuplesortstate *sort_in;    
    //对于下一个步骤,输入已拷贝
    Tuplesortstate *sort_out;    
    //排序结果的slot
    TupleTableSlot *sort_slot;    
    
    //------- 下面的列用于AGG_PLAIN和AGG_SORTED模式:
    //per-group指针的grouping set编号数组
    AggStatePerGroup *pergroups;    
    //当前组的第一个元组拷贝
    HeapTuple    grp_firstTuple; 
    
    //--------- 下面的列用于AGG_HASHED和AGG_MIXED模式:
    //是否已填充hash表?
    bool        table_filled;    
    //hash桶数?
    int            num_hashes;
    //相应的哈希表数据数组
    AggStatePerHash perhash;    
    //per-group指针的grouping set编号数组
    AggStatePerGroup *hash_pergroup;    
    
    //---------- agg输入表达式解析支持
#define FIELDNO_AGGSTATE_ALL_PERGROUPS 34
    //首先是->pergroups,然后是hash_pergroup
    AggStatePerGroup *all_pergroups;    
    //投影实现机制
    ProjectionInfo *combinedproj;    
} AggState;

//nodeag .c支持的基本选项
#define AGGSPLITOP_COMBINE        0x01    
#define AGGSPLITOP_SKIPFINAL    0x02    
#define AGGSPLITOP_SERIALIZE    0x04    
#define AGGSPLITOP_DESERIALIZE    0x08    

//支持的操作模式
typedef enum AggSplit
{
    
    //基本 : 非split聚合
    AGGSPLIT_SIMPLE = 0,
    
    //部分聚合的初始步骤,序列化
    AGGSPLIT_INITIAL_SERIAL = AGGSPLITOP_SKIPFINAL | AGGSPLITOP_SERIALIZE,
    
    //部分聚合的最终步骤,反序列化
    AGGSPLIT_FINAL_DESERIAL = AGGSPLITOP_COMBINE | AGGSPLITOP_DESERIALIZE
} AggSplit;

//测试AggSplit选择了哪些基本选项
#define DO_AGGSPLIT_COMBINE(as)        (((as) & AGGSPLITOP_COMBINE) != 0)
#define DO_AGGSPLIT_SKIPFINAL(as)    (((as) & AGGSPLITOP_SKIPFINAL) != 0)
#define DO_AGGSPLIT_SERIALIZE(as)    (((as) & AGGSPLITOP_SERIALIZE) != 0)
#define DO_AGGSPLIT_DESERIALIZE(as) (((as) & AGGSPLITOP_DESERIALIZE) != 0)

二、源码解读

advance_aggregates函数最终会调用ExecInterpExpr函数(先前已介绍),通过一系列的步骤得到结果.

static void
advance_aggregates(AggState *aggstate)
{
    bool        dummynull;
    ExecEvalExprSwitchContext(aggstate->phase->evaltrans,
                              aggstate->tmpcontext,
                              &dummynull);
}

#ifndef FRONTEND
static inline Datum
ExecEvalExprSwitchContext(ExprState *state,
                          ExprContext *econtext,
                          bool *isNull)
{
    Datum        retDatum;
    MemoryContext oldContext;
    oldContext = MemoryContextSwitchTo(econtext->ecxt_per_tuple_memory);
    retDatum = state->evalfunc(state, econtext, isNull);
    MemoryContextSwitchTo(oldContext);
    return retDatum;
}
#endif

Datum
ExecInterpExprStillValid(ExprState *state, ExprContext *econtext, bool *isNull)
{
    
    CheckExprStillValid(state, econtext);
    
    //在后续的执行中,跳过检查.
    state->evalfunc = (ExprStateEvalFunc) state->evalfunc_private;
    
    //执行解析函数,获取结果
    return state->evalfunc(state, econtext, isNull);
}
//evalfunc_private --> ExecInterpExpr

ExecInterpExpr
解析给定”econtext”在执行上下文中通过”state”标识的表达式.

//evalfunc_private --> ExecInterpExpr

static Datum
ExecInterpExpr(ExprState *state, ExprContext *econtext, bool *isnull)
{
    ExprEvalStep *op;
    TupleTableSlot *resultslot;
    TupleTableSlot *innerslot;
    TupleTableSlot *outerslot;
    TupleTableSlot *scanslot;
    
#if defined(EEO_USE_COMPUTED_GOTO)
    static const void *const dispatch_table[] = {
        &&CASE_EEOP_DONE,
        &&CASE_EEOP_INNER_FETCHSOME,
        &&CASE_EEOP_OUTER_FETCHSOME,
        &&CASE_EEOP_SCAN_FETCHSOME,
        &&CASE_EEOP_INNER_VAR,
        &&CASE_EEOP_OUTER_VAR,
        &&CASE_EEOP_SCAN_VAR,
        &&CASE_EEOP_INNER_SYSVAR,
        &&CASE_EEOP_OUTER_SYSVAR,
        &&CASE_EEOP_SCAN_SYSVAR,
        &&CASE_EEOP_WHOLEROW,
        &&CASE_EEOP_ASSIGN_INNER_VAR,
        &&CASE_EEOP_ASSIGN_OUTER_VAR,
        &&CASE_EEOP_ASSIGN_SCAN_VAR,
        &&CASE_EEOP_ASSIGN_TMP,
        &&CASE_EEOP_ASSIGN_TMP_MAKE_RO,
        &&CASE_EEOP_CONST,
        &&CASE_EEOP_FUNCEXPR,
        &&CASE_EEOP_FUNCEXPR_STRICT,
        &&CASE_EEOP_FUNCEXPR_FUSAGE,
        &&CASE_EEOP_FUNCEXPR_STRICT_FUSAGE,
        &&CASE_EEOP_BOOL_AND_STEP_FIRST,
        &&CASE_EEOP_BOOL_AND_STEP,
        &&CASE_EEOP_BOOL_AND_STEP_LAST,
        &&CASE_EEOP_BOOL_OR_STEP_FIRST,
        &&CASE_EEOP_BOOL_OR_STEP,
        &&CASE_EEOP_BOOL_OR_STEP_LAST,
        &&CASE_EEOP_BOOL_NOT_STEP,
        &&CASE_EEOP_QUAL,
        &&CASE_EEOP_JUMP,
        &&CASE_EEOP_JUMP_IF_NULL,
        &&CASE_EEOP_JUMP_IF_NOT_NULL,
        &&CASE_EEOP_JUMP_IF_NOT_TRUE,
        &&CASE_EEOP_NULLTEST_ISNULL,
        &&CASE_EEOP_NULLTEST_ISNOTNULL,
        &&CASE_EEOP_NULLTEST_ROWISNULL,
        &&CASE_EEOP_NULLTEST_ROWISNOTNULL,
        &&CASE_EEOP_BOOLTEST_IS_TRUE,
        &&CASE_EEOP_BOOLTEST_IS_NOT_TRUE,
        &&CASE_EEOP_BOOLTEST_IS_FALSE,
        &&CASE_EEOP_BOOLTEST_IS_NOT_FALSE,
        &&CASE_EEOP_PARAM_EXEC,
        &&CASE_EEOP_PARAM_EXTERN,
        &&CASE_EEOP_PARAM_CALLBACK,
        &&CASE_EEOP_CASE_TESTVAL,
        &&CASE_EEOP_MAKE_READONLY,
        &&CASE_EEOP_IOCOERCE,
        &&CASE_EEOP_DISTINCT,
        &&CASE_EEOP_NOT_DISTINCT,
        &&CASE_EEOP_NULLIF,
        &&CASE_EEOP_SQLVALUEFUNCTION,
        &&CASE_EEOP_CURRENTOFEXPR,
        &&CASE_EEOP_NEXTVALUEEXPR,
        &&CASE_EEOP_ARRAYEXPR,
        &&CASE_EEOP_ARRAYCOERCE,
        &&CASE_EEOP_ROW,
        &&CASE_EEOP_ROWCOMPARE_STEP,
        &&CASE_EEOP_ROWCOMPARE_FINAL,
        &&CASE_EEOP_MINMAX,
        &&CASE_EEOP_FIELDSELECT,
        &&CASE_EEOP_FIELDSTORE_DEFORM,
        &&CASE_EEOP_FIELDSTORE_FORM,
        &&CASE_EEOP_ARRAYREF_SUBSCRIPT,
        &&CASE_EEOP_ARRAYREF_OLD,
        &&CASE_EEOP_ARRAYREF_ASSIGN,
        &&CASE_EEOP_ARRAYREF_FETCH,
        &&CASE_EEOP_DOMAIN_TESTVAL,
        &&CASE_EEOP_DOMAIN_NOTNULL,
        &&CASE_EEOP_DOMAIN_CHECK,
        &&CASE_EEOP_CONVERT_ROWTYPE,
        &&CASE_EEOP_SCALARARRAYOP,
        &&CASE_EEOP_XMLEXPR,
        &&CASE_EEOP_AGGREF,
        &&CASE_EEOP_GROUPING_FUNC,
        &&CASE_EEOP_WINDOW_FUNC,
        &&CASE_EEOP_SUBPLAN,
        &&CASE_EEOP_ALTERNATIVE_SUBPLAN,
        &&CASE_EEOP_AGG_STRICT_DESERIALIZE,
        &&CASE_EEOP_AGG_DESERIALIZE,
        &&CASE_EEOP_AGG_STRICT_INPUT_CHECK,
        &&CASE_EEOP_AGG_INIT_TRANS,
        &&CASE_EEOP_AGG_STRICT_TRANS_CHECK,
        &&CASE_EEOP_AGG_PLAIN_TRANS_BYVAL,
        &&CASE_EEOP_AGG_PLAIN_TRANS,
        &&CASE_EEOP_AGG_ORDERED_TRANS_DATUM,
        &&CASE_EEOP_AGG_ORDERED_TRANS_TUPLE,
        &&CASE_EEOP_LAST
    };
    StaticAssertStmt(EEOP_LAST + 1 == lengthof(dispatch_table),
                     "dispatch_table out of whack with ExprEvalOp");
    if (unlikely(state == NULL))
        //如state == NULL,则调用PointerGetDatum
        return PointerGetDatum(dispatch_table);
#else
    Assert(state != NULL);
#endif                            
    
    //配置状态变量
    op = state->steps;
    resultslot = state->resultslot;
    innerslot = econtext->ecxt_innertuple;
    outerslot = econtext->ecxt_outertuple;
    scanslot = econtext->ecxt_scantuple;
#if defined(EEO_USE_COMPUTED_GOTO)
    EEO_DISPATCH();//分发
#endif
    EEO_SWITCH()
    {
        EEO_CASE(EEOP_DONE)
        {
            goto out;
        }
        EEO_CASE(EEOP_INNER_FETCHSOME)
        {
            
            slot_getsomeattrs(innerslot, op->d.fetch.last_var);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_OUTER_FETCHSOME)
        {
            slot_getsomeattrs(outerslot, op->d.fetch.last_var);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_SCAN_FETCHSOME)
        {
            slot_getsomeattrs(scanslot, op->d.fetch.last_var);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_INNER_VAR)
        {
            int            attnum = op->d.var.attnum;
            
            Assert(attnum >= 0 && attnum < innerslot->tts_nvalid);
            *op->resvalue = innerslot->tts_values[attnum];
            *op->resnull = innerslot->tts_isnull[attnum];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_OUTER_VAR)
        {
            int            attnum = op->d.var.attnum;
            
            Assert(attnum >= 0 && attnum < outerslot->tts_nvalid);
            *op->resvalue = outerslot->tts_values[attnum];
            *op->resnull = outerslot->tts_isnull[attnum];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_SCAN_VAR)
        {
            int            attnum = op->d.var.attnum;
            
            Assert(attnum >= 0 && attnum < scanslot->tts_nvalid);
            *op->resvalue = scanslot->tts_values[attnum];
            *op->resnull = scanslot->tts_isnull[attnum];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_INNER_SYSVAR)
        {
            int            attnum = op->d.var.attnum;
            Datum        d;
            
            Assert(innerslot->tts_tuple != NULL);
            Assert(innerslot->tts_tuple != &(innerslot->tts_minhdr));
            
            d = heap_getsysattr(innerslot->tts_tuple, attnum,
                                innerslot->tts_tupleDescriptor,
                                op->resnull);
            *op->resvalue = d;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_OUTER_SYSVAR)
        {
            int            attnum = op->d.var.attnum;
            Datum        d;
            
            Assert(outerslot->tts_tuple != NULL);
            Assert(outerslot->tts_tuple != &(outerslot->tts_minhdr));
            
            d = heap_getsysattr(outerslot->tts_tuple, attnum,
                                outerslot->tts_tupleDescriptor,
                                op->resnull);
            *op->resvalue = d;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_SCAN_SYSVAR)
        {
            int            attnum = op->d.var.attnum;
            Datum        d;
            
            Assert(scanslot->tts_tuple != NULL);
            Assert(scanslot->tts_tuple != &(scanslot->tts_minhdr));
            
            d = heap_getsysattr(scanslot->tts_tuple, attnum,
                                scanslot->tts_tupleDescriptor,
                                op->resnull);
            *op->resvalue = d;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_WHOLEROW)
        {
            
            ExecEvalWholeRowVar(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ASSIGN_INNER_VAR)
        {
            int            resultnum = op->d.assign_var.resultnum;
            int            attnum = op->d.assign_var.attnum;
            
            Assert(attnum >= 0 && attnum < innerslot->tts_nvalid);
            resultslot->tts_values[resultnum] = innerslot->tts_values[attnum];
            resultslot->tts_isnull[resultnum] = innerslot->tts_isnull[attnum];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ASSIGN_OUTER_VAR)
        {
            int            resultnum = op->d.assign_var.resultnum;
            int            attnum = op->d.assign_var.attnum;
            
            Assert(attnum >= 0 && attnum < outerslot->tts_nvalid);
            resultslot->tts_values[resultnum] = outerslot->tts_values[attnum];
            resultslot->tts_isnull[resultnum] = outerslot->tts_isnull[attnum];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ASSIGN_SCAN_VAR)
        {
            int            resultnum = op->d.assign_var.resultnum;
            int            attnum = op->d.assign_var.attnum;
            
            Assert(attnum >= 0 && attnum < scanslot->tts_nvalid);
            resultslot->tts_values[resultnum] = scanslot->tts_values[attnum];
            resultslot->tts_isnull[resultnum] = scanslot->tts_isnull[attnum];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ASSIGN_TMP)
        {
            int            resultnum = op->d.assign_tmp.resultnum;
            resultslot->tts_values[resultnum] = state->resvalue;
            resultslot->tts_isnull[resultnum] = state->resnull;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ASSIGN_TMP_MAKE_RO)
        {
            int            resultnum = op->d.assign_tmp.resultnum;
            resultslot->tts_isnull[resultnum] = state->resnull;
            if (!resultslot->tts_isnull[resultnum])
                resultslot->tts_values[resultnum] =
                    MakeExpandedObjectReadOnlyInternal(state->resvalue);
            else
                resultslot->tts_values[resultnum] = state->resvalue;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_CONST)
        {
            *op->resnull = op->d.constval.isnull;
            *op->resvalue = op->d.constval.value;
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_FUNCEXPR)
        {
            FunctionCallInfo fcinfo = op->d.func.fcinfo_data;
            Datum        d;
            fcinfo->isnull = false;
            d = op->d.func.fn_addr(fcinfo);
            *op->resvalue = d;
            *op->resnull = fcinfo->isnull;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_FUNCEXPR_STRICT)
        {
            FunctionCallInfo fcinfo = op->d.func.fcinfo_data;
            bool       *argnull = fcinfo->argnull;
            int            argno;
            Datum        d;
            
            for (argno = 0; argno < op->d.func.nargs; argno++)
            {
                if (argnull[argno])
                {
                    *op->resnull = true;
                    goto strictfail;
                }
            }
            fcinfo->isnull = false;
            d = op->d.func.fn_addr(fcinfo);
            *op->resvalue = d;
            *op->resnull = fcinfo->isnull;
    strictfail:
            EEO_NEXT();
        }
        EEO_CASE(EEOP_FUNCEXPR_FUSAGE)
        {
            
            ExecEvalFuncExprFusage(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_FUNCEXPR_STRICT_FUSAGE)
        {
            
            ExecEvalFuncExprStrictFusage(state, op, econtext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_BOOL_AND_STEP_FIRST)
        {
            *op->d.boolexpr.anynull = false;
            
            
        }
        EEO_CASE(EEOP_BOOL_AND_STEP)
        {
            if (*op->resnull)
            {
                *op->d.boolexpr.anynull = true;
            }
            else if (!DatumGetBool(*op->resvalue))
            {
                
                
                EEO_JUMP(op->d.boolexpr.jumpdone);
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_BOOL_AND_STEP_LAST)
        {
            if (*op->resnull)
            {
                
            }
            else if (!DatumGetBool(*op->resvalue))
            {
                
                
            }
            else if (*op->d.boolexpr.anynull)
            {
                *op->resvalue = (Datum) 0;
                *op->resnull = true;
            }
            else
            {
                
            }
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_BOOL_OR_STEP_FIRST)
        {
            *op->d.boolexpr.anynull = false;
            
            
        }
        EEO_CASE(EEOP_BOOL_OR_STEP)
        {
            if (*op->resnull)
            {
                *op->d.boolexpr.anynull = true;
            }
            else if (DatumGetBool(*op->resvalue))
            {
                
                
                EEO_JUMP(op->d.boolexpr.jumpdone);
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_BOOL_OR_STEP_LAST)
        {
            if (*op->resnull)
            {
                
            }
            else if (DatumGetBool(*op->resvalue))
            {
                
                
            }
            else if (*op->d.boolexpr.anynull)
            {
                *op->resvalue = (Datum) 0;
                *op->resnull = true;
            }
            else
            {
                
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_BOOL_NOT_STEP)
        {
            
            *op->resvalue = BoolGetDatum(!DatumGetBool(*op->resvalue));
            EEO_NEXT();
        }
        EEO_CASE(EEOP_QUAL)
        {
            
            
            if (*op->resnull ||
                !DatumGetBool(*op->resvalue))
            {
                
                *op->resnull = false;
                *op->resvalue = BoolGetDatum(false);
                EEO_JUMP(op->d.qualexpr.jumpdone);
            }
            
            EEO_NEXT();
        }
        EEO_CASE(EEOP_JUMP)
        {
            
            EEO_JUMP(op->d.jump.jumpdone);
        }
        EEO_CASE(EEOP_JUMP_IF_NULL)
        {
            
            if (*op->resnull)
                EEO_JUMP(op->d.jump.jumpdone);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_JUMP_IF_NOT_NULL)
        {
            
            if (!*op->resnull)
                EEO_JUMP(op->d.jump.jumpdone);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_JUMP_IF_NOT_TRUE)
        {
            
            if (*op->resnull || !DatumGetBool(*op->resvalue))
                EEO_JUMP(op->d.jump.jumpdone);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_NULLTEST_ISNULL)
        {
            *op->resvalue = BoolGetDatum(*op->resnull);
            *op->resnull = false;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_NULLTEST_ISNOTNULL)
        {
            *op->resvalue = BoolGetDatum(!*op->resnull);
            *op->resnull = false;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_NULLTEST_ROWISNULL)
        {
            
            ExecEvalRowNull(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_NULLTEST_ROWISNOTNULL)
        {
            
            ExecEvalRowNotNull(state, op, econtext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_BOOLTEST_IS_TRUE)
        {
            if (*op->resnull)
            {
                *op->resvalue = BoolGetDatum(false);
                *op->resnull = false;
            }
            
            EEO_NEXT();
        }
        EEO_CASE(EEOP_BOOLTEST_IS_NOT_TRUE)
        {
            if (*op->resnull)
            {
                *op->resvalue = BoolGetDatum(true);
                *op->resnull = false;
            }
            else
                *op->resvalue = BoolGetDatum(!DatumGetBool(*op->resvalue));
            EEO_NEXT();
        }
        EEO_CASE(EEOP_BOOLTEST_IS_FALSE)
        {
            if (*op->resnull)
            {
                *op->resvalue = BoolGetDatum(false);
                *op->resnull = false;
            }
            else
                *op->resvalue = BoolGetDatum(!DatumGetBool(*op->resvalue));
            EEO_NEXT();
        }
        EEO_CASE(EEOP_BOOLTEST_IS_NOT_FALSE)
        {
            if (*op->resnull)
            {
                *op->resvalue = BoolGetDatum(true);
                *op->resnull = false;
            }
            
            EEO_NEXT();
        }
        EEO_CASE(EEOP_PARAM_EXEC)
        {
            
            ExecEvalParamExec(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_PARAM_EXTERN)
        {
            
            ExecEvalParamExtern(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_PARAM_CALLBACK)
        {
            
            op->d.cparam.paramfunc(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_CASE_TESTVAL)
        {
            
            if (op->d.casetest.value)
            {
                *op->resvalue = *op->d.casetest.value;
                *op->resnull = *op->d.casetest.isnull;
            }
            else
            {
                *op->resvalue = econtext->caseValue_datum;
                *op->resnull = econtext->caseValue_isNull;
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_DOMAIN_TESTVAL)
        {
            
            if (op->d.casetest.value)
            {
                *op->resvalue = *op->d.casetest.value;
                *op->resnull = *op->d.casetest.isnull;
            }
            else
            {
                *op->resvalue = econtext->domainValue_datum;
                *op->resnull = econtext->domainValue_isNull;
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_MAKE_READONLY)
        {
            
            if (!*op->d.make_readonly.isnull)
                *op->resvalue =
                    MakeExpandedObjectReadOnlyInternal(*op->d.make_readonly.value);
            *op->resnull = *op->d.make_readonly.isnull;
            EEO_NEXT();
        }
        EEO_CASE(EEOP_IOCOERCE)
        {
            
            char       *str;
            
            if (*op->resnull)
            {
                
                str = NULL;
            }
            else
            {
                FunctionCallInfo fcinfo_out;
                fcinfo_out = op->d.iocoerce.fcinfo_data_out;
                fcinfo_out->arg[0] = *op->resvalue;
                fcinfo_out->argnull[0] = false;
                fcinfo_out->isnull = false;
                str = DatumGetCString(FunctionCallInvoke(fcinfo_out));
                
                Assert(!fcinfo_out->isnull);
            }
            
            if (!op->d.iocoerce.finfo_in->fn_strict || str != NULL)
            {
                FunctionCallInfo fcinfo_in;
                Datum        d;
                fcinfo_in = op->d.iocoerce.fcinfo_data_in;
                fcinfo_in->arg[0] = PointerGetDatum(str);
                fcinfo_in->argnull[0] = *op->resnull;
                
                fcinfo_in->isnull = false;
                d = FunctionCallInvoke(fcinfo_in);
                *op->resvalue = d;
                
                if (str == NULL)
                {
                    Assert(*op->resnull);
                    Assert(fcinfo_in->isnull);
                }
                else
                {
                    Assert(!*op->resnull);
                    Assert(!fcinfo_in->isnull);
                }
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_DISTINCT)
        {
            
            FunctionCallInfo fcinfo = op->d.func.fcinfo_data;
            
            if (fcinfo->argnull[0] && fcinfo->argnull[1])
            {
                
                *op->resvalue = BoolGetDatum(false);
                *op->resnull = false;
            }
            else if (fcinfo->argnull[0] || fcinfo->argnull[1])
            {
                
                *op->resvalue = BoolGetDatum(true);
                *op->resnull = false;
            }
            else
            {
                
                Datum        eqresult;
                fcinfo->isnull = false;
                eqresult = op->d.func.fn_addr(fcinfo);
                
                *op->resvalue = BoolGetDatum(!DatumGetBool(eqresult));
                *op->resnull = fcinfo->isnull;
            }
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_NOT_DISTINCT)
        {
            FunctionCallInfo fcinfo = op->d.func.fcinfo_data;
            if (fcinfo->argnull[0] && fcinfo->argnull[1])
            {
                *op->resvalue = BoolGetDatum(true);
                *op->resnull = false;
            }
            else if (fcinfo->argnull[0] || fcinfo->argnull[1])
            {
                *op->resvalue = BoolGetDatum(false);
                *op->resnull = false;
            }
            else
            {
                Datum        eqresult;
                fcinfo->isnull = false;
                eqresult = op->d.func.fn_addr(fcinfo);
                *op->resvalue = eqresult;
                *op->resnull = fcinfo->isnull;
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_NULLIF)
        {
            
            FunctionCallInfo fcinfo = op->d.func.fcinfo_data;
            
            if (!fcinfo->argnull[0] && !fcinfo->argnull[1])
            {
                Datum        result;
                fcinfo->isnull = false;
                result = op->d.func.fn_addr(fcinfo);
                
                if (!fcinfo->isnull && DatumGetBool(result))
                {
                    *op->resvalue = (Datum) 0;
                    *op->resnull = true;
                    EEO_NEXT();
                }
            }
            
            *op->resvalue = fcinfo->arg[0];
            *op->resnull = fcinfo->argnull[0];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_SQLVALUEFUNCTION)
        {
            
            ExecEvalSQLValueFunction(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_CURRENTOFEXPR)
        {
            
            ExecEvalCurrentOfExpr(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_NEXTVALUEEXPR)
        {
            
            ExecEvalNextValueExpr(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ARRAYEXPR)
        {
            
            ExecEvalArrayExpr(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ARRAYCOERCE)
        {
            
            ExecEvalArrayCoerce(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ROW)
        {
            
            ExecEvalRow(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ROWCOMPARE_STEP)
        {
            FunctionCallInfo fcinfo = op->d.rowcompare_step.fcinfo_data;
            Datum        d;
            
            if (op->d.rowcompare_step.finfo->fn_strict &&
                (fcinfo->argnull[0] || fcinfo->argnull[1]))
            {
                *op->resnull = true;
                EEO_JUMP(op->d.rowcompare_step.jumpnull);
            }
            
            fcinfo->isnull = false;
            d = op->d.rowcompare_step.fn_addr(fcinfo);
            *op->resvalue = d;
            
            if (fcinfo->isnull)
            {
                *op->resnull = true;
                EEO_JUMP(op->d.rowcompare_step.jumpnull);
            }
            *op->resnull = false;
            
            if (DatumGetInt32(*op->resvalue) != 0)
            {
                EEO_JUMP(op->d.rowcompare_step.jumpdone);
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ROWCOMPARE_FINAL)
        {
            int32        cmpresult = DatumGetInt32(*op->resvalue);
            RowCompareType rctype = op->d.rowcompare_final.rctype;
            *op->resnull = false;
            switch (rctype)
            {
                    
                case ROWCOMPARE_LT:
                    *op->resvalue = BoolGetDatum(cmpresult < 0);
                    break;
                case ROWCOMPARE_LE:
                    *op->resvalue = BoolGetDatum(cmpresult <= 0);
                    break;
                case ROWCOMPARE_GE:
                    *op->resvalue = BoolGetDatum(cmpresult >= 0);
                    break;
                case ROWCOMPARE_GT:
                    *op->resvalue = BoolGetDatum(cmpresult > 0);
                    break;
                default:
                    Assert(false);
                    break;
            }
            EEO_NEXT();
        }
        EEO_CASE(EEOP_MINMAX)
        {
            
            ExecEvalMinMax(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_FIELDSELECT)
        {
            
            ExecEvalFieldSelect(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_FIELDSTORE_DEFORM)
        {
            
            ExecEvalFieldStoreDeForm(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_FIELDSTORE_FORM)
        {
            
            ExecEvalFieldStoreForm(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ARRAYREF_SUBSCRIPT)
        {
            
            
            if (ExecEvalArrayRefSubscript(state, op))
            {
                EEO_NEXT();
            }
            else
            {
                
                EEO_JUMP(op->d.arrayref_subscript.jumpdone);
            }
        }
        EEO_CASE(EEOP_ARRAYREF_OLD)
        {
            
            
            ExecEvalArrayRefOld(state, op);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_ARRAYREF_ASSIGN)
        {
            
            ExecEvalArrayRefAssign(state, op);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_ARRAYREF_FETCH)
        {
            
            ExecEvalArrayRefFetch(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_CONVERT_ROWTYPE)
        {
            
            ExecEvalConvertRowtype(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_SCALARARRAYOP)
        {
            
            ExecEvalScalarArrayOp(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_DOMAIN_NOTNULL)
        {
            
            ExecEvalConstraintNotNull(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_DOMAIN_CHECK)
        {
            
            ExecEvalConstraintCheck(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_XMLEXPR)
        {
            
            ExecEvalXmlExpr(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_AGGREF)
        {
            
            AggrefExprState *aggref = op->d.aggref.astate;
            Assert(econtext->ecxt_aggvalues != NULL);
            *op->resvalue = econtext->ecxt_aggvalues[aggref->aggno];
            *op->resnull = econtext->ecxt_aggnulls[aggref->aggno];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_GROUPING_FUNC)
        {
            
            ExecEvalGroupingFunc(state, op);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_WINDOW_FUNC)
        {
            
            WindowFuncExprState *wfunc = op->d.window_func.wfstate;
            Assert(econtext->ecxt_aggvalues != NULL);
            *op->resvalue = econtext->ecxt_aggvalues[wfunc->wfuncno];
            *op->resnull = econtext->ecxt_aggnulls[wfunc->wfuncno];
            EEO_NEXT();
        }
        EEO_CASE(EEOP_SUBPLAN)
        {
            
            ExecEvalSubPlan(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_ALTERNATIVE_SUBPLAN)
        {
            
            ExecEvalAlternativeSubPlan(state, op, econtext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_STRICT_DESERIALIZE)
        {
            bool       *argnull = op->d.agg_deserialize.fcinfo_data->argnull;
            
            if (argnull[0])
                EEO_JUMP(op->d.agg_deserialize.jumpnull);
            
        }
        
        EEO_CASE(EEOP_AGG_DESERIALIZE)
        {
            FunctionCallInfo fcinfo = op->d.agg_deserialize.fcinfo_data;
            AggState   *aggstate = op->d.agg_deserialize.aggstate;
            MemoryContext oldContext;
            
            oldContext = MemoryContextSwitchTo(aggstate->tmpcontext->ecxt_per_tuple_memory);
            fcinfo->isnull = false;
            *op->resvalue = FunctionCallInvoke(fcinfo);
            *op->resnull = fcinfo->isnull;
            MemoryContextSwitchTo(oldContext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_STRICT_INPUT_CHECK)
        {
            int            argno;
            bool       *nulls = op->d.agg_strict_input_check.nulls;
            int            nargs = op->d.agg_strict_input_check.nargs;
            for (argno = 0; argno < nargs; argno++)
            {
                if (nulls[argno])
                    EEO_JUMP(op->d.agg_strict_input_check.jumpnull);
            }
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_INIT_TRANS)
        {
            AggState   *aggstate;
            AggStatePerGroup pergroup;
            aggstate = op->d.agg_init_trans.aggstate;
            pergroup = &aggstate->all_pergroups
                [op->d.agg_init_trans.setoff]
                [op->d.agg_init_trans.transno];
            
            if (pergroup->noTransValue)
            {
                AggStatePerTrans pertrans = op->d.agg_init_trans.pertrans;
                aggstate->curaggcontext = op->d.agg_init_trans.aggcontext;
                aggstate->current_set = op->d.agg_init_trans.setno;
                ExecAggInitGroup(aggstate, pertrans, pergroup);
                
                EEO_JUMP(op->d.agg_init_trans.jumpnull);
            }
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_STRICT_TRANS_CHECK)
        {
            AggState   *aggstate;
            AggStatePerGroup pergroup;
            aggstate = op->d.agg_strict_trans_check.aggstate;
            pergroup = &aggstate->all_pergroups
                [op->d.agg_strict_trans_check.setoff]
                [op->d.agg_strict_trans_check.transno];
            if (unlikely(pergroup->transValueIsNull))
                EEO_JUMP(op->d.agg_strict_trans_check.jumpnull);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_PLAIN_TRANS_BYVAL)
        {
            AggState   *aggstate;
            AggStatePerTrans pertrans;
            AggStatePerGroup pergroup;
            FunctionCallInfo fcinfo;
            MemoryContext oldContext;
            Datum        newVal;
            aggstate = op->d.agg_trans.aggstate;
            pertrans = op->d.agg_trans.pertrans;
            pergroup = &aggstate->all_pergroups
                [op->d.agg_trans.setoff]
                [op->d.agg_trans.transno];
            Assert(pertrans->transtypeByVal);
            fcinfo = &pertrans->transfn_fcinfo;
            
            aggstate->curaggcontext = op->d.agg_trans.aggcontext;
            aggstate->current_set = op->d.agg_trans.setno;
            
            aggstate->curpertrans = pertrans;
            
            oldContext = MemoryContextSwitchTo(aggstate->tmpcontext->ecxt_per_tuple_memory);
            fcinfo->arg[0] = pergroup->transValue;
            fcinfo->argnull[0] = pergroup->transValueIsNull;
            fcinfo->isnull = false; 
            newVal = FunctionCallInvoke(fcinfo);
            pergroup->transValue = newVal;
            pergroup->transValueIsNull = fcinfo->isnull;
            MemoryContextSwitchTo(oldContext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_PLAIN_TRANS)
        {
            AggState   *aggstate;
            AggStatePerTrans pertrans;
            AggStatePerGroup pergroup;
            FunctionCallInfo fcinfo;
            MemoryContext oldContext;
            Datum        newVal;
            aggstate = op->d.agg_trans.aggstate;
            pertrans = op->d.agg_trans.pertrans;
            pergroup = &aggstate->all_pergroups
                [op->d.agg_trans.setoff]
                [op->d.agg_trans.transno];
            Assert(!pertrans->transtypeByVal);
            fcinfo = &pertrans->transfn_fcinfo;
            
            aggstate->curaggcontext = op->d.agg_trans.aggcontext;
            aggstate->current_set = op->d.agg_trans.setno;
            
            aggstate->curpertrans = pertrans;
            
            oldContext = MemoryContextSwitchTo(aggstate->tmpcontext->ecxt_per_tuple_memory);
            fcinfo->arg[0] = pergroup->transValue;
            fcinfo->argnull[0] = pergroup->transValueIsNull;
            fcinfo->isnull = false; 
            newVal = FunctionCallInvoke(fcinfo);
            
            if (DatumGetPointer(newVal) != DatumGetPointer(pergroup->transValue))
                newVal = ExecAggTransReparent(aggstate, pertrans,
                                              newVal, fcinfo->isnull,
                                              pergroup->transValue,
                                              pergroup->transValueIsNull);
            pergroup->transValue = newVal;
            pergroup->transValueIsNull = fcinfo->isnull;
            MemoryContextSwitchTo(oldContext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_ORDERED_TRANS_DATUM)
        {
            
            ExecEvalAggOrderedTransDatum(state, op, econtext);
            EEO_NEXT();
        }
        
        EEO_CASE(EEOP_AGG_ORDERED_TRANS_TUPLE)
        {
            
            ExecEvalAggOrderedTransTuple(state, op, econtext);
            EEO_NEXT();
        }
        EEO_CASE(EEOP_LAST)
        {
            
            Assert(false);
            goto out;
        }
    }
out:
    *isnull = state->resnull;
    return state->resvalue;
}

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