1: # include   "../ingres.h"
   2: # include   "../symbol.h"
   3: # include   "../tree.h"
   4: # include   "../pipes.h"
   5: # include   "ovqp.h"
   6: 
   7: 
   8: /*
   9: **	SCAN
  10: **
  11: **	performs tuple by tuple scan of source reln or index reln
  12: **	within limits found by strategy routine.
  13: **	When the source reln tuple is obtained the interpreter is invoked
  14: **	to continue further processing
  15: **
  16: */
  17: 
  18: 
  19: scan()
  20: {
  21:     register    j, mode, domno;
  22:     char        *rlist; /* "result" list of query */
  23:     long        count;
  24:     long        tid, temptid;
  25:     char        agtup[MAXTUP], outtup1[MAXTUP];
  26:     int     qualfound, ok;
  27:     struct symbol   *interpret();
  28: 
  29: #	ifdef xOTR1
  30:     if (tTf(30, -1))
  31:     {
  32:         printf("SCAN\tScanr=%.12s\n", Scanr ? Scanr->relid : "(none)");
  33:         if (tTf(30, 4))
  34:             printf(" Alist=%l, Bylist=%l, Tlist=%l, Qlist=%l\n", Alist, Bylist, Tlist, Qlist);
  35:     }
  36: #	endif
  37: 
  38:     if (Result || Alist)
  39:     {
  40:         if (Result)
  41:             clr_tuple(Result, Outtup);
  42:         else
  43:         {
  44:             j = MAXTUP;
  45:             while (j--)
  46:                 Outtup[j] = 0;
  47:         }
  48:     }
  49: 
  50:     count = 0;
  51:     qualfound = EMPTY;
  52:     mode = Ov_qmode;
  53: 
  54:     /*
  55: 	** Check for identical source and result relations.
  56: 	** For modes mdREPL and mdDEL, Origtup must point
  57: 	** to the original (unmodified result tuple).
  58: 	**
  59: 	** If there is no Source or Result relations then
  60: 	** the code has no effect.
  61: 	*/
  62:     if (!bequal(Source->relid, Result->relid, MAXNAME))
  63:     {
  64:         Diffrel = TRUE;
  65:         Origtup = outtup1;
  66:     }
  67:     else
  68:     {
  69:         Diffrel = FALSE;
  70:         Origtup = Intup;
  71:     }
  72: 
  73:     /*  determine type of result list */
  74:     /* the only valid combinations are:
  75: 	**
  76: 	** Tlist=no	Alist=no	Bylist=no
  77: 	** Tlist=yes	Alist=no	Bylist=no
  78: 	** Tlist=no	Alist=yes	Bylist=no
  79: 	** Tlist=no	Alist=yes	Bylist=yes
  80: 	*/
  81:     rlist = (char *) (Tlist? Tlist: Alist);
  82:     if (Bylist)
  83:         rlist = 0;
  84: 
  85:     Counter= &count;
  86:     if (Bylist)
  87:     {
  88:         /*
  89: 		** For aggregate functions the result relation
  90: 		** is in the format:
  91: 		** domain 1 = I4 (used as a counter)
  92: 		** domain 2 through relatts - Agcount (by-domains)
  93: 		** remaining domains (the actual aggregate values)
  94: 		*/
  95: 
  96:         /* set up keys for the getequal */
  97:         /* domno must end with the domain number of the first aggregate */
  98:         for (domno = 2; domno <= Result->relatts - Agcount; domno++)
  99:             Result->relgiven[domno] = 1;
 100: 
 101:         Counter = (long *) Outtup;  /* first four bytes of Outtup is counter for Bylist */
 102:     }
 103: 
 104:     /*
 105: 	** check for constant qualification.
 106: 	** If the constant qual is true then remove
 107: 	** the qual to save reprocessing it.
 108: 	** If it is false then block further processing.
 109: 	*/
 110: 
 111:     ok = TRUE;
 112:     if (Qlist && Qualvc == 0)
 113:         if (*interpret(Qlist)->value)
 114:             Qlist = 0;  /* qual always true */
 115:         else
 116:             ok = FALSE; /* qual always false */
 117: 
 118: 
 119:     /* if no source relation, interpret target list */
 120:     if (!Scanr && ok)
 121:     {
 122:         /* there is no source relation and the qual is true */
 123:         qualfound = NONEMPTY;
 124:         Tend = Outtup;
 125:         /* if there is a rlist then process it. (There should always be one) */
 126:         if (rlist)
 127:         {
 128:             (*Counter)++;
 129:             interpret(rlist);
 130:         }
 131:         if (Tlist)
 132:             dispose(mode);
 133:         else
 134:             if (Userqry)
 135:                 Tupsfound++;
 136:     }
 137: 
 138:     if (Scanr && ok)
 139:     {
 140:         /* There is a source relation. Iterate through each tuple */
 141:         while (!(j = get(Scanr, &Lotid, &Hitid, Intup, NXTTUP)))
 142:         {
 143: #			ifdef xOTR1
 144:             if (tTf(30, 5))
 145:             {
 146:                 if (Scanr != Source)
 147:                     printf("Sec Index:");
 148:                 else
 149:                     printf("Intup:");
 150:                 printup(Scanr, Intup);
 151:             }
 152: #			endif
 153:             Intid = Lotid;
 154:             if (Scanr != Source)
 155:             {
 156:                 /* make sure index tuple is part of the solution */
 157:                 if (!indexcheck())
 158:                     /* index keys don't match what we want */
 159:                     continue;
 160:                 bmove(Intup + Scanr->relwid - TIDLEN, &tid, TIDLEN);
 161:                 if (j = get(Source, &tid, &temptid, &Intup, CURTUP))
 162:                     syserr("scan:indx get %d %.12s", j, Scanr->relid);
 163: #				ifdef xOTR1
 164:                 if (tTf(30, 6))
 165:                 {
 166:                     printf("Intup:");
 167:                     printup(Source, Intup);
 168:                 }
 169: #				endif
 170:                 Intid = tid;
 171:             }
 172: 
 173:             if ( !Qlist || *interpret(Qlist)->value)
 174:             {
 175:                 qualfound = NONEMPTY;
 176:                 Tend = Outtup;
 177:                 if (rlist)
 178:                 {
 179:                     (*Counter)++;
 180:                     interpret(rlist);
 181:                 }
 182:                 if (Tlist)
 183:                     dispose(mode);
 184:                 else
 185:                     if (Userqry)
 186:                         Tupsfound++;
 187: 
 188:                 if (!Targvc)    /* constant Target list */
 189:                     break;
 190: 
 191:                 /* process Bylist if any */
 192:                 if (Bylist)
 193:                 {
 194:                     interpret(Bylist);
 195:                     if ((j = getequal(Result, Outtup, agtup, &Uptid)) < 0)
 196:                         syserr("scan:getequal %d,%.12s", j, Result->relid);
 197: 
 198:                     if (!j)
 199:                     {
 200:                         /* match on bylist */
 201:                         bmove(agtup, Outtup, Result->relwid);
 202:                         mode = mdREPL;
 203:                         (*Counter)++;
 204:                     }
 205:                     else
 206:                     {
 207:                         /* first of this bylist */
 208:                         mode = mdAPP;
 209:                         *Counter = 1;
 210:                     }
 211: 
 212:                     Tend = Outtup + Result->reloff[domno];
 213:                     interpret(Alist);
 214:                     dispose(mode);
 215:                 }
 216:             }
 217:         }
 218: 
 219:         if (j < 0)
 220:             syserr("scan:get prim %d %.12s", j, Source->relid);
 221:     }
 222:     if (Result)
 223:     {
 224:         if (j = noclose(Result))
 225:             syserr("scan:noclose %d %.12s", j, Result->relid);
 226:     }
 227:     return (qualfound);
 228: }
 229: 
 230: dispose(mode)
 231: {
 232:     register int    i;
 233: 
 234:     i = 0;
 235: 
 236:     if (!Result)
 237:     {
 238:         if (Equel)
 239:             equeleol(EOTUP);
 240:         else
 241:             printeol();
 242:     }
 243:     else
 244:     {
 245: #		ifdef xOTR1
 246:         if (tTf(30, -1))
 247:         {
 248:             if (tTf(30, 1))
 249:                 printf("mode=%d,",mode);
 250:             if (tTf(30, 2) && (mode == mdREPL || mode == mdDEL))
 251:                 printf("Uptid:%s, ",locv(Uptid));
 252:             if (tTf(30, 3))
 253:                 if (mode == mdDEL)
 254:                     printup(Source, Intup);
 255:                 else
 256:                     printup(Result, Outtup);
 257:         }
 258: #		endif
 259: 
 260:         /* SPOOL UPDATES OF EXISTING USER RELNS TO BATCH PROCESSOR */
 261:         if (Buflag)
 262:         {
 263:             addbatch(&Uptid, Outtup, Origtup);
 264:             return;
 265:         }
 266: 
 267:         /* PERFORM ALL OTHER OPERATIONS DIRECTLY */
 268:         switch (mode)
 269:         {
 270:           case mdRETR:
 271:           case mdAPP:
 272:             if ((i = insert(Result, &Uptid, Outtup, NODUPS)) < 0)
 273:                 syserr("dispose:insert %d %.12s", i, Result->relid);
 274:             break;
 275: 
 276:           case mdREPL:
 277:             if ((i = replace(Result, &Uptid, Outtup, NODUPS)) < 0)
 278:                 syserr("dispose:replace %d %.12s", i, Result->relid);
 279:             break;
 280: 
 281:           case mdDEL:
 282:             if ((i = delete(Result, &Uptid)) < 0)
 283:                 syserr("dispose:delete %d %.12s", i, Result->relid);
 284:             break;
 285: 
 286:           default:
 287:             syserr("dispose:bad mode %d", mode);
 288:         }
 289:     }
 290: 
 291:     if (Userqry && i == 0)
 292:         Tupsfound++;
 293: }

Defined functions

dispose defined in line 230; used 3 times
Last modified: 1995-03-01
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