execJunk.c File Reference

#include "postgres.h"
#include "executor/executor.h"

Include dependency graph for execJunk.c:

Go to the source code of this file.

Functions
JunkFilter *	ExecInitJunkFilter (List *targetList, TupleTableSlot *slot)
JunkFilter *	ExecInitJunkFilterConversion (List *targetList, TupleDesc cleanTupType, TupleTableSlot *slot)
AttrNumber	ExecFindJunkAttribute (JunkFilter *junkfilter, const char *attrName)
AttrNumber	ExecFindJunkAttributeInTlist (List *targetlist, const char *attrName)
TupleTableSlot *	ExecFilterJunk (JunkFilter *junkfilter, TupleTableSlot *slot)

Function Documentation

ExecFilterJunk()

TupleTableSlot* ExecFilterJunk	(	JunkFilter *	junkfilter,
		TupleTableSlot *	slot
	)

Definition at line 247 of file execJunk.c.

{
    TupleTableSlot *resultSlot;
    AttrNumber *cleanMap;
    TupleDesc   cleanTupType;
    int         cleanLength;
    int         i;
    Datum      *values;
    bool       *isnull;
    Datum      *old_values;
    bool       *old_isnull;
 
    /*
     * Extract all the values of the old tuple.
     */
    slot_getallattrs(slot);
    old_values = slot->tts_values;
    old_isnull = slot->tts_isnull;
 
    /*
     * get info from the junk filter
     */
    cleanTupType = junkfilter->jf_cleanTupType;
    cleanLength = cleanTupType->natts;
    cleanMap = junkfilter->jf_cleanMap;
    resultSlot = junkfilter->jf_resultSlot;
 
    /*
     * Prepare to build a virtual result tuple.
     */
    ExecClearTuple(resultSlot);
    values = resultSlot->tts_values;
    isnull = resultSlot->tts_isnull;
 
    /*
     * Transpose data into proper fields of the new tuple.
     */
    for (i = 0; i < cleanLength; i++)
    {
        int         j = cleanMap[i];
 
        if (j == 0)
        {
            values[i] = (Datum) 0;
            isnull[i] = true;
        }
        else
        {
            values[i] = old_values[j - 1];
            isnull[i] = old_isnull[j - 1];
        }
    }
 
    /*
     * And return the virtual tuple.
     */
    return ExecStoreVirtualTuple(resultSlot);
}

References ExecClearTuple(), ExecStoreVirtualTuple(), i, j, JunkFilter::jf_cleanMap, JunkFilter::jf_cleanTupType, JunkFilter::jf_resultSlot, TupleDescData::natts, slot_getallattrs(), TupleTableSlot::tts_isnull, TupleTableSlot::tts_values, and values.

Referenced by ExecEvalWholeRowVar(), ExecutePlan(), and sqlfunction_receive().

ExecFindJunkAttribute()

AttrNumber ExecFindJunkAttribute	(	JunkFilter *	junkfilter,
		const char *	attrName
	)

Definition at line 210 of file execJunk.c.

{
    return ExecFindJunkAttributeInTlist(junkfilter->jf_targetList, attrName);
}

References ExecFindJunkAttributeInTlist(), and JunkFilter::jf_targetList.

ExecFindJunkAttributeInTlist()

AttrNumber ExecFindJunkAttributeInTlist	(	List *	targetlist,
		const char *	attrName
	)

Definition at line 222 of file execJunk.c.

{
    ListCell   *t;
 
    foreach(t, targetlist)
    {
        TargetEntry *tle = lfirst(t);
 
        if (tle->resjunk && tle->resname &&
            (strcmp(tle->resname, attrName) == 0))
        {
            /* We found it ! */
            return tle->resno;
        }
    }
 
    return InvalidAttrNumber;
}

References InvalidAttrNumber, lfirst, and TargetEntry::resno.

Referenced by create_foreign_modify(), ExecBuildAuxRowMark(), ExecFindJunkAttribute(), and ExecInitModifyTable().

ExecInitJunkFilter()

JunkFilter* ExecInitJunkFilter	(	List *	targetList,
		TupleTableSlot *	slot
	)

Definition at line 60 of file execJunk.c.

{
    JunkFilter *junkfilter;
    TupleDesc   cleanTupType;
    int         cleanLength;
    AttrNumber *cleanMap;
 
    /*
     * Compute the tuple descriptor for the cleaned tuple.
     */
    cleanTupType = ExecCleanTypeFromTL(targetList);
 
    /*
     * Use the given slot, or make a new slot if we weren't given one.
     */
    if (slot)
        ExecSetSlotDescriptor(slot, cleanTupType);
    else
        slot = MakeSingleTupleTableSlot(cleanTupType, &TTSOpsVirtual);
 
    /*
     * Now calculate the mapping between the original tuple's attributes and
     * the "clean" tuple's attributes.
     *
     * The "map" is an array of "cleanLength" attribute numbers, i.e. one
     * entry for every attribute of the "clean" tuple. The value of this entry
     * is the attribute number of the corresponding attribute of the
     * "original" tuple.  (Zero indicates a NULL output attribute, but we do
     * not use that feature in this routine.)
     */
    cleanLength = cleanTupType->natts;
    if (cleanLength > 0)
    {
        AttrNumber  cleanResno;
        ListCell   *t;
 
        cleanMap = (AttrNumber *) palloc(cleanLength * sizeof(AttrNumber));
        cleanResno = 0;
        foreach(t, targetList)
        {
            TargetEntry *tle = lfirst(t);
 
            if (!tle->resjunk)
            {
                cleanMap[cleanResno] = tle->resno;
                cleanResno++;
            }
        }
        Assert(cleanResno == cleanLength);
    }
    else
        cleanMap = NULL;
 
    /*
     * Finally create and initialize the JunkFilter struct.
     */
    junkfilter = makeNode(JunkFilter);
 
    junkfilter->jf_targetList = targetList;
    junkfilter->jf_cleanTupType = cleanTupType;
    junkfilter->jf_cleanMap = cleanMap;
    junkfilter->jf_resultSlot = slot;
 
    return junkfilter;
}

References Assert, ExecCleanTypeFromTL(), ExecSetSlotDescriptor(), JunkFilter::jf_cleanMap, JunkFilter::jf_cleanTupType, JunkFilter::jf_resultSlot, JunkFilter::jf_targetList, lfirst, makeNode, MakeSingleTupleTableSlot(), TupleDescData::natts, palloc(), TargetEntry::resno, and TTSOpsVirtual.

Referenced by ExecInitWholeRowVar(), init_sql_fcache(), and InitPlan().

ExecInitJunkFilterConversion()

JunkFilter* ExecInitJunkFilterConversion	(	List *	targetList,
		TupleDesc	cleanTupType,
		TupleTableSlot *	slot
	)

Definition at line 137 of file execJunk.c.

{
    JunkFilter *junkfilter;
    int         cleanLength;
    AttrNumber *cleanMap;
    ListCell   *t;
    int         i;
 
    /*
     * Use the given slot, or make a new slot if we weren't given one.
     */
    if (slot)
        ExecSetSlotDescriptor(slot, cleanTupType);
    else
        slot = MakeSingleTupleTableSlot(cleanTupType, &TTSOpsVirtual);
 
    /*
     * Calculate the mapping between the original tuple's attributes and the
     * "clean" tuple's attributes.
     *
     * The "map" is an array of "cleanLength" attribute numbers, i.e. one
     * entry for every attribute of the "clean" tuple. The value of this entry
     * is the attribute number of the corresponding attribute of the
     * "original" tuple.  We store zero for any deleted attributes, marking
     * that a NULL is needed in the output tuple.
     */
    cleanLength = cleanTupType->natts;
    if (cleanLength > 0)
    {
        cleanMap = (AttrNumber *) palloc0(cleanLength * sizeof(AttrNumber));
        t = list_head(targetList);
        for (i = 0; i < cleanLength; i++)
        {
            if (TupleDescAttr(cleanTupType, i)->attisdropped)
                continue;       /* map entry is already zero */
            for (;;)
            {
                TargetEntry *tle = lfirst(t);
 
                t = lnext(targetList, t);
                if (!tle->resjunk)
                {
                    cleanMap[i] = tle->resno;
                    break;
                }
            }
        }
    }
    else
        cleanMap = NULL;
 
    /*
     * Finally create and initialize the JunkFilter struct.
     */
    junkfilter = makeNode(JunkFilter);
 
    junkfilter->jf_targetList = targetList;
    junkfilter->jf_cleanTupType = cleanTupType;
    junkfilter->jf_cleanMap = cleanMap;
    junkfilter->jf_resultSlot = slot;
 
    return junkfilter;
}

References ExecSetSlotDescriptor(), i, JunkFilter::jf_cleanMap, JunkFilter::jf_cleanTupType, JunkFilter::jf_resultSlot, JunkFilter::jf_targetList, lfirst, list_head(), lnext(), makeNode, MakeSingleTupleTableSlot(), TupleDescData::natts, palloc0(), TargetEntry::resno, TTSOpsVirtual, and TupleDescAttr.

Referenced by init_sql_fcache().