DB: Add function to query stats from db

inc/lektor/database.h

@@ -192,7 +192,9 @@ bool database_sticker_delete        (volatile sqlite3 *db, const char *name);
 bool database_sticker_delete_specify(volatile sqlite3 *sb, const char *type, int uri,
                                      const char *name);
 bool database_sticker_set           (volatile sqlite3 *db, const char *type, const char *name,
-                                     int uri,
-                                     int value);
+                                     int uri, int value);
+
+/* Get some stats from the database */
+bool database_stats(volatile sqlite3 *db, int *authors, int *sources, int *karas);
 
 #endif /* __LKT_DATABASE_H__ */

src/database/update.c

@@ -321,3 +321,23 @@ sqlite_just_exec(database_stamp, "UPDATE misc SET last_update = strftime('%s','n
 sqlite_just_exec(database_updated,
                  "UPDATE misc SET last_end_update = strftime('%s','now'), update_job = update_job + 1;")
 #undef sqlite_just_exec
+
+bool
+database_stats(volatile sqlite3 *db, int *authors, int *sources, int *karas)
+{
+    static const char *SQL =
+        "SELECT"
+        " (SELECT COUNT(DISTINCT author_name) FROM kara),"
+        " (SELECT COUNT(DISTINCT source_name) FROM kara),"
+        " (SELECT COUNT(id) FROM kara);";
+    sqlite3_stmt *stmt = 0;
+
+    SQLITE_PREPARE(db, stmt, SQL, error);
+    SQLITE_STEP_ROW(db, stmt, error);
+
+    sqlite3_finalize(stmt);
+    return true;
+error:
+    sqlite3_finalize(stmt);
+    return false;
+}