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/************* tdbvir C++ Program Source Code File (.CPP) **************/
/* PROGRAM NAME: tdbvir.cpp Version 1.2 */
/* (C) Copyright to the author Olivier BERTRAND 2014-2017 */
/* This program are the VIR classes DB execution routines. */
/***********************************************************************/
/***********************************************************************/
/* Include relevant sections of the MariaDB header file. */
/***********************************************************************/
#include <my_global.h>
/***********************************************************************/
/* Include application header files: */
/* global.h is header containing all global declarations. */
/* plgdbsem.h is header containing the DB application declarations. */
/* xtable.h is header containing the TDBASE declarations. */
/* tdbvir.h is header containing the VIR classes declarations. */
/***********************************************************************/
#include "global.h"
#include "plgdbsem.h"
#include "filter.h"
#include "xtable.h"
//#include "reldef.h"
#include "colblk.h"
#include "mycat.h" // for FNC_COL
#include "tabvir.h"
#include "resource.h" // for IDS_COLUMNS
/***********************************************************************/
/* Return the unique column definition to MariaDB. */
/***********************************************************************/
PQRYRES VirColumns(PGLOBAL g, bool info)
{
int buftyp[] = {TYPE_STRING, TYPE_SHORT, TYPE_STRING,
TYPE_INT, TYPE_STRING, TYPE_STRING};
XFLD fldtyp[] = {FLD_NAME, FLD_TYPE, FLD_TYPENAME,
FLD_PREC, FLD_KEY, FLD_EXTRA};
unsigned int length[] = {8, 4, 16, 4, 16, 16};
int i, n, ncol = sizeof(buftyp) / sizeof(int);
PQRYRES qrp;
PCOLRES crp;
n = (info) ? 0 : 1;
/**********************************************************************/
/* Allocate the structures used to refer to the result set. */
/**********************************************************************/
if (!(qrp = PlgAllocResult(g, ncol, n, IDS_COLUMNS + 3,
buftyp, fldtyp, length, false, true)))
return NULL;
// Some columns must be renamed before info
for (i = 0, crp = qrp->Colresp; crp; crp = crp->Next)
switch (++i) {
case 5: crp->Name = "Key"; break;
case 6: crp->Name = "Extra"; break;
} // endswitch i
if (info)
return qrp;
/**********************************************************************/
/* Now get the results into blocks. */
/**********************************************************************/
// Set column name
crp = qrp->Colresp; // Column_Name
crp->Kdata->SetValue("n", 0);
// Set type, type name, precision
crp = crp->Next; // Data_Type
crp->Kdata->SetValue(TYPE_INT, 0);
crp = crp->Next; // Type_Name
crp->Kdata->SetValue(GetTypeName(TYPE_INT), 0);
crp = crp->Next; // Precision
crp->Kdata->SetValue(11, 0);
crp = crp->Next; // Key
crp->Kdata->SetValue("KEY", 0);
crp = crp->Next; // Extra
crp->Kdata->SetValue("SPECIAL=ROWID", 0);
qrp->Nblin = 1;
/**********************************************************************/
/* Return the result pointer for use by discovery routines. */
/**********************************************************************/
return qrp;
} // end of VirColumns
/* --------------------------- Class VIRDEF --------------------------- */
/***********************************************************************/
/* GetTable: makes a new Table Description Block. */
/***********************************************************************/
PTDB VIRDEF::GetTable(PGLOBAL g, MODE)
{
// Column blocks will be allocated only when needed.
if (Catfunc == FNC_COL)
return new(g) TDBVICL(this);
else
return new(g) TDBVIR(this);
} // end of GetTable
/* ------------------------ TDBVIR functions ------------------------- */
/***********************************************************************/
/* Implementation of the TDBVIR class. */
/***********************************************************************/
TDBVIR::TDBVIR(PVIRDEF tdp) : TDBASE(tdp)
{
Size = (tdp->GetElemt()) ? tdp->GetElemt() : 1;
N = -1;
} // end of TDBVIR constructor
/***********************************************************************/
/* Analyze the filter and reset the size limit accordingly. */
/* This is possible when a filter contains predicates implying the */
/* special column ROWID. Here we just test for when no more good */
/* records can be met in the remaining of the table. */
/***********************************************************************/
int TDBVIR::TestFilter(PFIL filp, bool nop)
{
int i, op = filp->GetOpc(), n = 0, type[2] = {0,0};
int l1 = 0, l2, limit = Size;
PXOB arg[2] = {NULL,NULL};
if (op == OP_GT || op == OP_GE || op == OP_LT || op == OP_LE) {
for (i = 0; i < 2; i++) {
arg[i] = filp->Arg(i);
switch (filp->GetArgType(i)) {
case TYPE_CONST:
if ((l1 = arg[i]->GetIntValue()) >= 0)
type[i] = 1;
break;
case TYPE_COLBLK:
if (((PCOL)arg[i])->GetTo_Tdb() == this &&
((PCOL)arg[i])->GetAmType() == TYPE_AM_ROWID)
type[i] = 2;
break;
default:
break;
} // endswitch ArgType
if (!type[i])
break;
n += type[i];
} // endfor i
if (n == 3) {
// If true it will be ok to delete the filter
BOOL ok = (filp == To_Filter);
if (type[0] == 1)
// Make it always a Column-op-Value
switch (op) {
case OP_GT: op = OP_LT; break;
case OP_GE: op = OP_LE; break;
case OP_LT: op = OP_GT; break;
case OP_LE: op = OP_GE; break;
} // endswitch op
if (!nop) switch (op) {
case OP_LT: l1--; /* fall through */
case OP_LE: limit = l1; break;
default: ok = false;
} // endswitch op
else switch (op) {
case OP_GE: l1--; /* fall through */
case OP_GT: limit = l1; break;
default: ok = false;
} // endswitch op
limit = MY_MIN(MY_MAX(0, limit), Size);
// Just one where clause such as Rowid < limit;
if (ok)
To_Filter = NULL;
} else
limit = Size;
} else if ((op == OP_AND && !nop) || (op == OP_OR && nop)) {
l1 = TestFilter((PFIL)filp->Arg(0), nop);
l2 = TestFilter((PFIL)filp->Arg(1), nop);
limit = MY_MIN(l1, l2);
} else if (op == OP_NOT)
limit = TestFilter((PFIL)filp->Arg(0), !nop);
return limit;
} // end of TestFilter
/***********************************************************************/
/* Allocate source column description block. */
/***********************************************************************/
PCOL TDBVIR::MakeCol(PGLOBAL g, PCOLDEF cdp, PCOL cprec, int n)
{
PCOL colp = NULL;
if (cdp->IsVirtual()) {
colp = new(g) VIRCOL(cdp, this, cprec, n);
} else strcpy(g->Message,
"Virtual tables accept only special or virtual columns");
return colp;
} // end of MakeCol
/***********************************************************************/
/* VIR Access Method opening routine. */
/***********************************************************************/
bool TDBVIR::OpenDB(PGLOBAL g)
{
if (Use == USE_OPEN) {
// Table already open
N = -1;
return false;
} // endif use
if (Mode != MODE_READ) {
strcpy(g->Message, "Virtual tables are read only");
return true;
} // endif Mode
/*********************************************************************/
/* Analyze the filter and refine Size accordingly. */
/*********************************************************************/
if (To_Filter)
Size = TestFilter(To_Filter, false);
return false;
} // end of OpenDB
/***********************************************************************/
/* Data Base read routine for the VIR access method. */
/***********************************************************************/
int TDBVIR::ReadDB(PGLOBAL)
{
return (++N >= Size) ? RC_EF : RC_OK;
} // end of ReadDB
/***********************************************************************/
/* WriteDB: Data Base write routine for the VIR access methods. */
/***********************************************************************/
int TDBVIR::WriteDB(PGLOBAL g)
{
snprintf(g->Message, sizeof(g->Message), MSG(VIR_READ_ONLY), To_Def->GetType());
return RC_FX;
} // end of WriteDB
/***********************************************************************/
/* Data Base delete line routine for the VIR access methods. */
/***********************************************************************/
int TDBVIR::DeleteDB(PGLOBAL g, int)
{
snprintf(g->Message, sizeof(g->Message), MSG(VIR_NO_DELETE), To_Def->GetType());
return RC_FX;
} // end of DeleteDB
/* ---------------------------- VIRCOL ------------------------------- */
/***********************************************************************/
/* VIRCOL public constructor. */
/***********************************************************************/
VIRCOL::VIRCOL(PCOLDEF cdp, PTDB tdbp, PCOL cprec, int i, PCSZ)
: COLBLK(cdp, tdbp, i)
{
if (cprec) {
Next = cprec->GetNext();
cprec->SetNext(this);
} else {
Next = tdbp->GetColumns();
tdbp->SetColumns(this);
} // endif cprec
} // end of VIRCOL constructor
/***********************************************************************/
/* ReadColumn: */
/***********************************************************************/
void VIRCOL::ReadColumn(PGLOBAL g)
{
// This should never be called
snprintf(g->Message, sizeof(g->Message), "ReadColumn: Column %s is not virtual", Name);
throw (int)TYPE_COLBLK;
} // end of ReadColumn
/* ---------------------------TDBVICL class -------------------------- */
/***********************************************************************/
/* GetResult: Get the list the VIRTUAL table columns. */
/***********************************************************************/
PQRYRES TDBVICL::GetResult(PGLOBAL g)
{
return VirColumns(g, false);
} // end of GetResult
/* ------------------------- End of Virtual -------------------------- */
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