1: # include   "../ingres.h"
   2: # include   "../aux.h"
   3: # include   "../symbol.h"
   4: # include   "../access.h"
   5: # include   "../batch.h"
   6: 
   7: /*
   8: **	Update reads a batch file written by the
   9: **	access method routines (openbatch, addbatch, closebatch)
  10: **	and performs the updates stored in the file.
  11: **
  12: **	It assumes that it is running in the database. It
  13: **	is driven by the data in the Batchhd struct (see ../batch.h).
  14: **	If the relation has a secondary index then update calls
  15: **	secupdate. As a last step the batch file is removed.
  16: **
  17: **	The global flag Batch_recovery is tested in case
  18: **	of an error. It should be FALSE if update is being
  19: **	run as the dbu deferred update processor. It should
  20: **	be TRUE if it is being used as part of the recovery
  21: **	procedure.
  22: */
  23: 
  24: update()
  25: {
  26:     register int        i, mode;
  27:     struct descriptor   rel;
  28:     long            oldtid, tupcnt;
  29:     char            oldtup[MAXTUP], newtup[MAXTUP];
  30:     char            *batchname();
  31:     extern int      Dburetflag;
  32:     extern struct retcode   Dburetcode;
  33: 
  34: #	ifdef xZTR1
  35:     if (tTf(15, -1))
  36:         printf("Update on %s\n", batchname());
  37: #	endif
  38:     /* set up to read batchhd */
  39:     Batch_cnt = BATCHSIZE;  /* force a read on next getbatch */
  40:     Batch_dirty = FALSE;
  41:     if ((Batch_fp = open(batchname(), 2)) < 0)
  42:         syserr("prim:can't open %s", batchname());
  43:     getbatch(&Batchhd, sizeof Batchhd);
  44: 
  45:     tupcnt = Batchhd.num_updts;
  46: #	ifdef xZTR1
  47:     if (tTf(15, 0))
  48:         printf("rel=%s tups=%s\n", Batchhd.rel_name, locv(tupcnt));
  49: #	endif
  50:     Dburetflag = TRUE;
  51:     Dburetcode.rc_tupcount = 0;
  52:     if (!tupcnt)
  53:     {
  54:         rmbatch();
  55:         return (1);
  56:     }
  57: 
  58:     /* update the primary relation */
  59:     if (i = openr(&rel, 2, Batchhd.rel_name))
  60:         syserr("prim:can't openr %s %d", Batchhd.rel_name, i);
  61:     mode = Batchhd.mode_up;
  62: 
  63:     while (tupcnt--)
  64:     {
  65:         getbatch(&oldtid, Batchhd.tido_size);   /* read old tid */
  66:         getbatch(oldtup, Batchhd.tupo_size);    /* and portions of old tuple */
  67:         getbatch(newtup, Batchhd.tupn_size);    /* and the newtup */
  68: 
  69:         switch (mode)
  70:         {
  71: 
  72:           case mdDEL:
  73:             if ((i = delete(&rel, &oldtid)) < 0)
  74:                 syserr("prim:bad del %d %s", i, Batchhd.rel_name);
  75:             break;
  76: 
  77:           case mdREPL:
  78:             if (i = replace(&rel, &oldtid, newtup, TRUE))
  79:             {
  80:                 /* if newtuple is a duplicate, then ok */
  81:                 if (i == 1)
  82:                     break;
  83:                 /* if this is recovery and oldtup not there, try to insert newtup */
  84:                 if (Batch_recovery && i == 2)
  85:                     goto upinsert;
  86:                 syserr("prim:Non-functional replace on %s (%d)", i, Batchhd.rel_name);
  87:             }
  88:             Dburetcode.rc_tupcount++;
  89:             break;
  90: 
  91:           case mdAPP:
  92:           upinsert:
  93:             if ((i = insert(&rel, &oldtid, newtup, TRUE)) < 0)
  94:                 syserr("prim:bad insert %d %s", i, Batchhd.rel_name);
  95:             break;
  96: 
  97:           default:
  98:             syserr("prim:impossible mode %d", mode);
  99:         }
 100:         putbatch(&oldtid, Batchhd.tidn_size);   /* write new tid if necessary */
 101:     }
 102:     /* fix the tupchanged count if delete or append */
 103:     if (mode != mdREPL)
 104:         Dburetcode.rc_tupcount = rel.reladds >= 0 ? rel.reladds : -rel.reladds;
 105:     /* close the relation but secupdate will still use the decriptor */
 106:     if (i = closer(&rel))
 107:         syserr("prim:close err %d %s", i, Batchhd.rel_name);
 108:     batchflush();
 109: 
 110:     /* if this relation is indexed, update the indexes */
 111:     if (rel.relindxd > 0)
 112:         secupdate(&rel);
 113:     rmbatch();
 114: 
 115: #	ifdef xZTR1
 116:     if (tTf(15, 2))
 117:         printf("%s tups changed\n", locv(Dburetcode.rc_tupcount));
 118: #	endif
 119:     return (0);
 120: }

Defined functions

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