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1.1 root 1: # include <ingres.h>
2: # include <aux.h>
3: # include <catalog.h>
4: # include <access.h>
5: # include <tree.h>
6: # include <symbol.h>
7: # include "qrymod.h"
8: # include <sccs.h>
9:
10: SCCSID(@(#)integrity.c 7.1 2/5/81)
11:
12: /*
13: ** INTEGRITY.C -- Integrity Constraint Processor
14: **
15: ** This module contains the integrity constraint processor. This
16: ** processor modifies the query to add integrity constraints.
17: **
18: ** Currently only single-variable aggregate-free constraints are
19: ** handled. Thus the algorithm is reduced to scanning the tree
20: ** for each variable modified and appending the constraints for
21: ** that variable to the tree.
22: **
23: ** Parameters:
24: ** none
25: **
26: ** Returns:
27: ** The root of the modified tree.
28: **
29: ** Side Effects:
30: ** Much relation I/O.
31: ** Modifies the tree in place, so the previous one is
32: ** lost.
33: **
34: ** Trace Flags:
35: ** 40 -> 49
36: */
37:
38: extern DESC Intdes;
39:
40: QTREE *
41: integrity(root)
42: QTREE *root;
43: {
44: register QTREE *r;
45: int dset[8];
46: register QTREE *p;
47: register int i;
48: auto QTREE *iqual;
49: struct integrity inttup, intkey;
50: struct tup_id hitid, lotid;
51: extern QTREE *gettree();
52: extern QTREE *norml();
53:
54: # ifdef xQTR1
55: tTfp(40, -1, "\n->INTEGRITY\n");
56: # endif
57:
58: r = root;
59:
60: /*
61: ** Check to see if we should apply the integrity
62: ** algorithm.
63: **
64: ** This means checking to insure that we have an update
65: ** and seeing if any integrity constraints apply.
66: */
67:
68: if (Qt.qt_qmode == mdRETR ||
69: (Qt.qt_rangev[Qt.qt_resvar].rngvdesc->reldum.relstat & S_INTEG) == 0)
70: {
71: # ifdef xQTR2
72: tTfp(40, 0, "->INTEGRITY: no integ\n");
73: # endif
74: return(r);
75: }
76:
77: /*
78: ** Create a set of the domains updated in this query.
79: */
80:
81: for (i = 0; i < 8; i++)
82: dset[i] = 0;
83: for (p = r->left; p != NULL && p->sym.type != TREE; p = p->left)
84: {
85: # ifdef xQTR3
86: if (p->sym.type != RESDOM)
87: syserr("integrity: RESDOM %d", p->sym.type);
88: # endif
89: lsetbit(p->sym.value.sym_resdom.resno, dset);
90: }
91:
92: # ifdef xQTR3
93: if (p == NULL)
94: syserr("integrity: NULL LHS");
95: # endif
96: # ifdef xQTR1
97: if (tTf(40, 1))
98: pr_set(dset, "dset");
99: # endif
100:
101: /*
102: ** Scan integrity catalog for possible tuples. If found,
103: ** include them in the integrity qualification.
104: */
105:
106: iqual = NULL;
107: opencatalog("integrities", 0);
108: setkey(&Intdes, &intkey, Qt.qt_rangev[Qt.qt_resvar].rngvdesc->reldum.relid, INTRELID);
109: setkey(&Intdes, &intkey, Qt.qt_rangev[Qt.qt_resvar].rngvdesc->reldum.relowner, INTRELOWNER);
110: find(&Intdes, EXACTKEY, &lotid, &hitid, &intkey);
111:
112: while ((i = get(&Intdes, &lotid, &hitid, &inttup, TRUE)) == 0)
113: {
114: if (kcompare(&Intdes, &intkey, &inttup) != 0)
115: continue;
116:
117: # ifdef xQTR1
118: if (tTf(40, 2))
119: printup(&Intdes, &inttup);
120: # endif
121:
122: /* check for some domain set overlap */
123: for (i = 0; i < 8; i++)
124: if ((dset[i] & inttup.intdomset[i]) != 0)
125: break;
126: if (i >= 8)
127: continue;
128:
129: /* some domain matches, include in integrity qual */
130: i = Qt.qt_resvar;
131: p = gettree(Qt.qt_rangev[i].rngvdesc->reldum.relid,
132: Qt.qt_rangev[i].rngvdesc->reldum.relowner,
133: mdINTEG, inttup.inttree, FALSE);
134: # ifdef xQTR1
135: if (tTf(40, 3))
136: treepr(p, "int_qual");
137: # endif
138:
139: /* trim off (null) target list */
140: p = p->right;
141:
142: /* merge the 'integrity' var into the Qt.qt_resvar */
143: i = inttup.intresvar;
144: if (Qt.qt_remap[i] >= 0)
145: i = Qt.qt_remap[i];
146: mergevar(i, Qt.qt_resvar, p);
147:
148: /* add to integrity qual */
149: if (iqual == NULL)
150: iqual = p;
151: else
152: appqual(p, iqual);
153: }
154: if (i < 0)
155: syserr("integrity: get %d", i);
156:
157: /*
158: ** Clean up the integrity qualification so that it will merge
159: ** nicely into the tree, and then append it to the user's
160: ** qualification.
161: */
162:
163: if (iqual != NULL)
164: {
165: /* replace VAR nodes by corresponding user afcn */
166: subsvars(&iqual, Qt.qt_resvar, r->left, Qt.qt_qmode);
167:
168: /* append to tree and normalize */
169: appqual(iqual, r);
170: # ifdef xQTR3
171: if (tTf(40, 8))
172: treepr(r, "Unnormalized tree");
173: # endif
174: r->right = norml(trimqlend(r->right));
175: }
176:
177: # ifdef xQTR1
178: if (tTf(40, 15))
179: treepr(r, "INTEGRITY->");
180: # endif
181:
182: return (r);
183: }
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