Ticket #3113: mythtv-CleanupRecordedTables-recordedmarkup_and_recordedseek-20070221.patch

programs/mythbackend/housekeeper.cpp

@@ -362 +362 @@
         "recordedprogram",
         "recordedrating",
         "recordedcredits",
+        "recordedmarkup",
+        "recordedseek",
         "" }; // This blank entry must exist, do not remove.
     QString table = tables[tableIndex];
-   
+
+    // Because recordedseek can have millions of rows, we don't want to JOIN it
+    // with recorded.  Instead, pull out DISTINCT chanid and starttime into a
+    // temporary table (resulting in tens, hundreds, or--at most--a few
+    // thousand rows) for the JOIN
+    QString querystr;
+    querystr = "CREATE TEMPORARY TABLE IF NOT EXISTS temprecordedcleanup ("
+               "chanid int(10) unsigned NOT NULL default '0',"
+               "starttime datetime NOT NULL default '0000-00-00 00:00:00' );";
+
+    if (!query.exec(querystr))
+    {
+        MythContext::DBError("Housekeeper Creating Temporary Table", query);
+        return;
+    }
+
     while (table != "")
     {
+        query.prepare(QString("TRUNCATE TABLE temprecordedcleanup;"));
+        if (!query.exec() || !query.isActive())
+        {
+            MythContext::DBError("Housekeeper Truncating Temporary Table",
+                                 query);
+            return;
+        }
+
+        query.prepare(QString("INSERT INTO temprecordedcleanup "
+                              "( chanid, starttime ) "
+                              "SELECT DISTINCT chanid, starttime "
+                              "FROM %1;")
+                              .arg(table));
+
+        if (!query.exec() || !query.isActive())
+        {
+            MythContext::DBError("HouseKeeper Cleaning Recorded Tables", query);
+            return;
+        }
+
         query.prepare(QString("SELECT DISTINCT p.chanid, p.starttime "
-                              "FROM %1 p LEFT JOIN recorded r "
+                              "FROM temprecordedcleanup p "
+                              "LEFT JOIN recorded r "
                               "ON p.chanid = r.chanid "
                               "AND p.starttime = r.progstart "
-                              "WHERE r.chanid IS NULL;")
-                              .arg(table));
+                              "WHERE r.chanid IS NULL;"));
         if (!query.exec() || !query.isActive())
         {
             MythContext::DBError("HouseKeeper Cleaning Recorded Tables", query);
@@ -393 +430 @@
         tableIndex++;
         table = tables[tableIndex];
     }
+
+    if (!query.exec("DROP TABLE temprecordedcleanup;"))
+        MythContext::DBError("Housekeeper Dropping Temporary Table", query);
+
 }
 
 void HouseKeeper::CleanupProgramListings(void)