Differences From:

File src/descendents.c part of check-in [e15fe43153] - A new decendent finding algorithm is (hopefully) faster. Changes to the timeline are in process and might not yet work. by drh on 2007-08-31 20:14:33. [view]

To:

File src/descendents.c part of check-in [abce5105e2] - Updates to the timeline routines. Added the pqueue module. by drh on 2007-09-01 01:55:50. Also file src/descendents.c part of check-in [bbcb6326c9] - Pulled in the navbar and timeline changes. by aku on 2007-09-17 00:58:51. [view]

@@ -67,8 +67,67 @@
     }
   }
   bag_clear(&pending);
   bag_clear(&seen);
+}
+
+/*
+** Load the record ID rid and up to N-1 closest ancestors into
+** the "ok" table.
+*/
+void compute_ancestors(int rid, int N){
+  Bag seen;
+  PQueue queue;
+  bag_init(&seen);
+  pqueue_init(&queue);
+  bag_insert(&seen, rid);
+  pqueue_insert(&queue, rid, 0.0);
+  while( (N--)>0 && (rid = pqueue_extract(&queue))!=0 ){
+    Stmt q;
+    db_multi_exec("INSERT OR IGNORE INTO ok VALUES(%d)", rid);
+    db_prepare(&q,
+       "SELECT a.pid, b.mtime FROM plink a LEFT JOIN plink b ON b.cid=a.pid"
+       " WHERE a.cid=%d", rid
+    );
+    while( db_step(&q)==SQLITE_ROW ){
+      int pid = db_column_int(&q, 0);
+      double mtime = db_column_double(&q, 1);
+      if( bag_insert(&seen, pid) ){
+        pqueue_insert(&queue, pid, -mtime);
+      }
+    }
+    db_finalize(&q);
+  }
+  bag_clear(&seen);
+  pqueue_clear(&queue);
+}
+
+/*
+** Load the record ID rid and up to N-1 closest descendents into
+** the "ok" table.
+*/
+void compute_descendents(int rid, int N){
+  Bag seen;
+  PQueue queue;
+  bag_init(&seen);
+  pqueue_init(&queue);
+  bag_insert(&seen, rid);
+  pqueue_insert(&queue, rid, 0.0);
+  while( (N--)>0 && (rid = pqueue_extract(&queue))!=0 ){
+    Stmt q;
+    db_multi_exec("INSERT OR IGNORE INTO ok VALUES(%d)", rid);
+    db_prepare(&q,"SELECT cid, mtime FROM plink WHERE pid=%d", rid);
+    while( db_step(&q)==SQLITE_ROW ){
+      int pid = db_column_int(&q, 0);
+      double mtime = db_column_double(&q, 1);
+      if( bag_insert(&seen, pid) ){
+        pqueue_insert(&queue, pid, mtime);
+      }
+    }
+    db_finalize(&q);
+  }
+  bag_clear(&seen);
+  pqueue_clear(&queue);
 }
 
 /*
 ** COMMAND:  leaves