www

commit 50a0b2d36c5a6b5debdf65b3647df71a94020b81
parent e7d7d2a94354b1135bd17c95cad5073669de65da
Author: Dan Stillman <dstillman@zotero.org>
Date:   Sat, 16 Feb 2013 23:06:31 -0500

Apparently the dummy transaction hasn't been necessary since 2007 or so

https://bugzilla.mozilla.org/show_bug.cgi?id=380345

Diffstat:
M
chrome/content/zotero/xpcom/db.js
 | 
76
++--------------------------------------------------------------------------
M
chrome/content/zotero/xpcom/zotero.js
 | 
2
--

2 files changed, 2 insertions(+), 76 deletions(-)
diff --git a/chrome/content/zotero/xpcom/db.js b/chrome/content/zotero/xpcom/db.js
@@ -23,7 +23,8 @@
     ***** END LICENSE BLOCK *****
 */
 
-// Exclusive locking mode (default) prevents access to Zotero database while Firefox is open.
+// Exclusive locking mode (default) prevents access to Zotero database while Zotero is open
+// and speeds up DB access (http://www.sqlite.org/pragma.html#pragma_locking_mode).
 // Normal mode is more convenient for development, but risks database corruption, particularly if
 // the same database is accessed simultaneously by multiple Zotero instances.
 const DB_LOCK_EXCLUSIVE = true;
@@ -793,7 +794,6 @@ Zotero.DBConnection.prototype.checkException = function (e) {
 
 Zotero.DBConnection.prototype.closeDatabase = function () {
 	if(this._connection) {
-		this.stopDummyStatement();
 		this._connection.close();
 		return true;
 	}
@@ -875,14 +875,10 @@ Zotero.DBConnection.prototype.backupDatabase = function (suffix) {
 	
 	// Turn off DB locking before backup and reenable after, since otherwise
 	// the lock is lost
-	var hadDummyStatement = !!this._dummyStatement;
 	try {
 		if (DB_LOCK_EXCLUSIVE) {
 			this.query("PRAGMA locking_mode=NORMAL");
 		}
-		if (hadDummyStatement) {
-			this.stopDummyStatement();
-		}
 		
 		var store = Components.classes["@mozilla.org/storage/service;1"].
 			getService(Components.interfaces.mozIStorageService);
@@ -897,9 +893,6 @@ Zotero.DBConnection.prototype.backupDatabase = function (suffix) {
 		if (DB_LOCK_EXCLUSIVE) {
 			this.query("PRAGMA locking_mode=EXCLUSIVE");
 		}
-		if (hadDummyStatement) {
-			this.startDummyStatement();
-		}
 	}
 	
 	// Opened database files can't be moved on Windows, so we have to skip
@@ -968,71 +961,6 @@ Zotero.DBConnection.prototype.backupDatabase = function (suffix) {
 }
 
 
-/*
- * Keep the SQLite shared cache live between transactions with a dummy statement,
- * which speeds up DB access dramatically (at least on Windows and Linux--OS X
- * seems to be much faster already, perhaps due to its own disk cache)
- *
- * This is the same technique used by Mozilla code. The one downside is that it
- * prevents schema changes, so this is called after schema updating. If the
- * schema really needs to be updated at another point, use stopDummyStatement().
- *
- * See http://developer.mozilla.org/en/docs/Storage:Performance for more info.
- */
-Zotero.DBConnection.prototype.startDummyStatement = function () {
-	try {
-		if (!this._dummyConnection) {
-			this._debug("Opening database '" + this._dbName + "' for dummy statement");
-			// Get the storage service
-			var store = Components.classes["@mozilla.org/storage/service;1"].
-				getService(Components.interfaces.mozIStorageService);
-			var file = Zotero.getZoteroDatabase(this._dbName);
-			this._dummyConnection = store.openDatabase(file);
-		}
-		
-		if (this._dummyStatement) {
-			Zotero.debug("Dummy statement is already open");
-			return;
-		}
-		
-		Zotero.debug("Initializing dummy statement for '" + this._dbName + "'");
-		
-		var sql = "CREATE TABLE IF NOT EXISTS zoteroDummyTable (id INTEGER PRIMARY KEY)";
-		this._dummyConnection.executeSimpleSQL(sql);
-		
-		sql = "INSERT OR IGNORE INTO zoteroDummyTable VALUES (1)";
-		this._dummyConnection.executeSimpleSQL(sql);
-		
-		sql = "SELECT id FROM zoteroDummyTable LIMIT 1"
-		this._dummyStatement = this._dummyConnection.createStatement(sql)
-		this._dummyStatement.executeStep()
-	
-	}
-	catch (e) {
-		Components.utils.reportError(e);
-		Zotero.debug(e);
-	}
-}
-
-
-/*
- * Stop the dummy statement temporarily to allow for schema changess
- *
- * The statement needs to be started again or performance will suffer.
- */
-Zotero.DBConnection.prototype.stopDummyStatement = function () {
-	if (!this._dummyStatement) {
-		return;
-	}
-	
-	Zotero.debug("Stopping dummy statement for '" + this._dbName + "'");
-	this._dummyStatement.finalize();
-	this._dummyConnection.close();
-	delete this._dummyConnection;
-	delete this._dummyStatement;
-}
-
-
 /**
  * Determine the necessary data type for SQLite parameter binding
  *
diff --git a/chrome/content/zotero/xpcom/zotero.js b/chrome/content/zotero/xpcom/zotero.js
@@ -640,8 +640,6 @@ Components.utils.import("resource://gre/modules/Services.jsm");
 			}
 		}
 		
-		Zotero.DB.startDummyStatement();
-		
 		// Populate combined tables for custom types and fields -- this is likely temporary
 		if (!upgraded && !updated) {
 			Zotero.Schema.updateCustomTables();