- When saving rows in the table content view, only include those fields which have altered values in the UPDATE query, improving speed and reducing the chance of issues when copying queries or altering rapidly changing tables. This addresses Issue #527; thanks to Tobias Mollstam for contributing a patch which prompted this update.

 - Rename SPTableContent's "addRowToDB" to "saveRowToTable" for clarity, and clean up the code for speed and clarity
 - Correctly save numeric fields as NULL if the value is blanked

3 files changed, 95 insertions, 86 deletions

diff --git a/Source/SPCopyTable.m b/Source/SPCopyTable.m
index 7a132348..6b9383ab 100644
--- a/Source/SPCopyTable.m
+++ b/Source/SPCopyTable.m
@@ -973,8 +973,8 @@ NSInteger kBlobAsImageFile = 4;
 
 		// Save the current line if it's the last field in the table
 		if ( [self numberOfColumns] - 1 == column ) {
-			if([[self delegate] respondsToSelector:@selector(addRowToDB)])
-				[[self delegate] addRowToDB];
+			if([[self delegate] respondsToSelector:@selector(saveRowToTable)])
+				[[self delegate] saveRowToTable];
 			[[self window] makeFirstResponder:self];
 		} else {
 			// Select the next field for editing
@@ -991,8 +991,8 @@ NSInteger kBlobAsImageFile = 4;
 
 		// Save the current line if it's the last field in the table
 		if ( column < 1 ) {
-			if([[self delegate] respondsToSelector:@selector(addRowToDB)])
-				[[self delegate] addRowToDB];
+			if([[self delegate] respondsToSelector:@selector(saveRowToTable)])
+				[[self delegate] saveRowToTable];
 			[[self window] makeFirstResponder:self];
 		} else {
 			// Select the previous field for editing
@@ -1010,8 +1010,8 @@ NSInteger kBlobAsImageFile = 4;
 			return YES;
 
 		[[control window] makeFirstResponder:control];
-		if([[self delegate] isKindOfClass:[SPTableContent class]] && ![self isCellEditingMode] && [[self delegate] respondsToSelector:@selector(addRowToDB)])
-			[[self delegate] addRowToDB];
+		if([[self delegate] isKindOfClass:[SPTableContent class]] && ![self isCellEditingMode] && [[self delegate] respondsToSelector:@selector(saveRowToTable)])
+			[[self delegate] saveRowToTable];
 		return YES;
 
 	}
@@ -1028,10 +1028,10 @@ NSInteger kBlobAsImageFile = 4;
 		if (newRow>=[[self delegate] numberOfRowsInTableView:self]) return YES; //check if we're already at the end of the list
 
 		[[control window] makeFirstResponder:control];
-		if([[self delegate] isKindOfClass:[SPTableContent class]] && ![self isCellEditingMode] && [[self delegate] respondsToSelector:@selector(addRowToDB)])
-			[[self delegate] addRowToDB];
+		if([[self delegate] isKindOfClass:[SPTableContent class]] && ![self isCellEditingMode] && [[self delegate] respondsToSelector:@selector(saveRowToTable)])
+			[[self delegate] saveRowToTable];
 
-		if (newRow>=[[self delegate] numberOfRowsInTableView:self]) return YES; //check again. addRowToDB could reload the table and change the number of rows
+		if (newRow>=[[self delegate] numberOfRowsInTableView:self]) return YES; //check again. saveRowToTable could reload the table and change the number of rows
 		if (tableStorage && column>=[tableStorage columnCount]) return YES;     //the column count could change too
 
 		[self selectRowIndexes:[NSIndexSet indexSetWithIndex:newRow] byExtendingSelection:NO];
@@ -1051,10 +1051,10 @@ NSInteger kBlobAsImageFile = 4;
 		NSUInteger newRow = row-1;
 
 		[[control window] makeFirstResponder:control];
-		if([[self delegate] isKindOfClass:[SPTableContent class]] && ![self isCellEditingMode] && [[self delegate] respondsToSelector:@selector(addRowToDB)])
-			[[self delegate] addRowToDB];
+		if([[self delegate] isKindOfClass:[SPTableContent class]] && ![self isCellEditingMode] && [[self delegate] respondsToSelector:@selector(saveRowToTable)])
+			[[self delegate] saveRowToTable];
 
-		if (newRow>=[[self delegate] numberOfRowsInTableView:self]) return YES; // addRowToDB could reload the table and change the number of rows
+		if (newRow>=[[self delegate] numberOfRowsInTableView:self]) return YES; // saveRowToTable could reload the table and change the number of rows
 		if (tableStorage && column>=[tableStorage columnCount]) return YES;     //the column count could change too
 
 		[self selectRowIndexes:[NSIndexSet indexSetWithIndex:newRow] byExtendingSelection:NO];
diff --git a/Source/SPTableContent.h b/Source/SPTableContent.h
index 1dc4caf9..e3fd8a53 100644
--- a/Source/SPTableContent.h
+++ b/Source/SPTableContent.h
@@ -197,7 +197,7 @@
 - (void)clickLinkArrowTask:(SPTextAndLinkCell *)theArrowCell;
 - (IBAction)setCompareTypes:(id)sender;
 - (void)processResultIntoDataStorage:(MCPStreamingResult *)theResult approximateRowCount:(NSUInteger)targetRowCount;
-- (BOOL)addRowToDB;
+- (BOOL)saveRowToTable;
 - (NSString *)argumentForRow:(NSInteger)row;
 - (NSString *)argumentForRow:(NSInteger)row excludingLimits:(BOOL)excludeLimits;
 - (NSString *)argumentForRow:(NSUInteger)rowIndex ofTable:(NSString *)tableForColumn andDatabase:(NSString *)database includeBlobs:(BOOL)includeBlobs;
diff --git a/Source/SPTableContent.m b/Source/SPTableContent.m
index 1e9bdf5f..1f4889d7 100644
--- a/Source/SPTableContent.m
+++ b/Source/SPTableContent.m
@@ -2370,116 +2370,125 @@
 
 
 /**
- * Tries to write a new row to the database.
- * Returns YES if row is written to database, otherwise NO; also returns YES if no row
- * is being edited and nothing has to be written to the database.
+ * Tries to write a new row to the table.
+ * Returns YES if row is written to table, otherwise NO; also returns YES if no row
+ * is being edited or nothing has to be written to the table.
  */
-- (BOOL)addRowToDB
+- (BOOL)saveRowToTable
 {
 
-	if([tablesListInstance tableType] == SPTableTypeView) return;
+	// Only handle tables - views should be handled per-cell.
+	if ([tablesListInstance tableType] == SPTableTypeView) return NO;
 
-	NSMutableString *queryString;
-	id rowObject;
-	NSMutableString *rowValue = [NSMutableString string];
-	NSString *currentTime = [[NSDate date] descriptionWithCalendarFormat:@"%H:%M:%S" timeZone:nil locale:nil];
-	BOOL prefsLoadBlobsAsNeeded = [prefs boolForKey:SPLoadBlobsAsNeeded];
-	NSInteger i;
-
-	if ( !isEditingRow || currentlyEditingRow == -1) {
-		return YES;
-	}
-
-	[[NSNotificationCenter defaultCenter] postNotificationOnMainThreadWithName:@"SMySQLQueryWillBePerformed" object:tableDocumentInstance];
+	// If no row is being edited, return success.
+	if (!isEditingRow) return YES;
 
-	// If editing, compare the new row to the old row and if they are identical finish editing without saving.
+	// If editing, quickly compare the new row to the old row and if they are identical finish editing without saving.
 	if (!isEditingNewRow && [oldRow isEqualToArray:[tableValues rowContentsAtIndex:currentlyEditingRow]]) {
 		isEditingRow = NO;
 		currentlyEditingRow = -1;
-		[[NSNotificationCenter defaultCenter] postNotificationOnMainThreadWithName:@"SMySQLQueryHasBeenPerformed" object:tableDocumentInstance];
 		return YES;
 	}
 
-	NSMutableArray *fieldValues = [[NSMutableArray alloc] init];
-
-	// Get the field values
-	for ( i = 0 ; i < [dataColumns count] ; i++ ) {
+	// Iterate through the row contents, constructing the (ordered) arrays of keys and values to be saved
+	NSMutableArray *rowFieldsToSave = [[NSMutableArray alloc] initWithCapacity:[dataColumns count]];
+	NSMutableArray *rowValuesToSave = [[NSMutableArray alloc] initWithCapacity:[dataColumns count]];
+	NSInteger i;
+	id rowObject;
+	for (i = 0; i < [dataColumns count]; i++) {
 		rowObject = [tableValues cellDataAtRow:currentlyEditingRow column:i];
 
-		// Add not loaded placeholders directly for easy comparison when added
-		if (prefsLoadBlobsAsNeeded && !isEditingNewRow && [rowObject isSPNotLoaded])
-		{
-			[fieldValues addObject:[SPNotLoaded notLoaded]];
-			continue;
+		// Skip "not loaded" cells entirely - these only occur when editing tables when the
+		// preference setting is enabled, and don't need to be saved back to the table.
+		if ([rowObject isSPNotLoaded]) continue;
+
+		// Prepare to derive the value to save, also tracking whether the field has changed.
+		BOOL fieldValueHasChanged = (isEditingNewRow || ![rowObject isEqual:NSArrayObjectAtIndex(oldRow, i)]);
+		NSString *fieldValue;
+		NSString *fieldTypeGroup = [NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"typegrouping"];
 
 		// Catch CURRENT_TIMESTAMP automatic updates - if the row is new and the cell value matches
 		// the default value, or if the cell hasn't changed, update the current timestamp.
-		} else if ([[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"onupdatetimestamp"] integerValue]
-					&& (   (isEditingNewRow && [rowObject isEqualTo:[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"default"]])
-						|| (!isEditingNewRow && [rowObject isEqualTo:NSArrayObjectAtIndex(oldRow, i)])))
+		if ([[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"onupdatetimestamp"] integerValue]
+			&& (	(isEditingNewRow && [rowObject isEqualTo:[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"default"]])
+					|| (!isEditingNewRow && [rowObject isEqualTo:NSArrayObjectAtIndex(oldRow, i)])))
 		{
-			[rowValue setString:@"CURRENT_TIMESTAMP"];
-
-		} else if ( [rowObject isNSNull]
-				|| ([rowObject isMemberOfClass:[NSString class]] && [[rowObject description] isEqualToString:@""]) ) {
+			fieldValue = @"CURRENT_TIMESTAMP";
+			fieldValueHasChanged = YES;
+
+		// Use NULL when the user has entered the nullValue string defined in the preferences,
+		// or when a numeric field is empty.
+		} else if ([rowObject isNSNull]
+					|| (([fieldTypeGroup isEqualToString:@"float"] || [fieldTypeGroup isEqualToString:@"integer"])
+						&& [[rowObject description] isEqualToString:@""]))
+		{
+			fieldValue = @"NULL";
 
-			//NULL when user entered the nullValue string defined in the prefs or when a number field isn't set
-			//	problem: when a number isn't set, sequel-pro enters 0
-			//	-> second if argument isn't necessary!
-			[rowValue setString:@"NULL"];
-		} else if ( [[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"typegrouping"] isEqualToString:@"geometry"] ) {
-			[rowValue setString:([rowObject isKindOfClass:[MCPGeometryData class]]) ? [[rowObject wktString] getGeomFromTextString] : [(NSString*)rowObject getGeomFromTextString]];
+		// Convert geometry values to their string values
+		} else if ([fieldTypeGroup isEqualToString:@"geometry"]) {
+			fieldValue = ([rowObject isKindOfClass:[MCPGeometryData class]]) ? [[rowObject wktString] getGeomFromTextString] : [(NSString*)rowObject getGeomFromTextString];
+	
 		// Convert the object to a string (here we can add special treatment for date-, number- and data-fields)
 		} else {
 
-			// I don't believe any of these class matches are ever met at present.
-			if ( [rowObject isKindOfClass:[NSCalendarDate class]] ) {
-				[rowValue setString:[NSString stringWithFormat:@"'%@'", [mySQLConnection prepareString:[rowObject description]]]];
-			} else if ( [rowObject isKindOfClass:[NSNumber class]] ) {
-				[rowValue setString:[rowObject stringValue]];
-			} else if ( [rowObject isKindOfClass:[NSData class]] ) {
-				[rowValue setString:[NSString stringWithFormat:@"X'%@'", [mySQLConnection prepareBinaryData:rowObject]]];
+			// I believe these class matches are not ever met at present.
+			if ([rowObject isKindOfClass:[NSCalendarDate class]]) {
+				fieldValue = [NSString stringWithFormat:@"'%@'", [mySQLConnection prepareString:[rowObject description]]];
+			} else if ([rowObject isKindOfClass:[NSNumber class]]) {
+				fieldValue = [rowObject stringValue];
+
+			// Convert data to its hex representation
+			} else if ([rowObject isKindOfClass:[NSData class]]) {
+				fieldValue = [NSString stringWithFormat:@"X'%@'", [mySQLConnection prepareBinaryData:rowObject]];
+
 			} else {
 				if ([[rowObject description] isEqualToString:@"CURRENT_TIMESTAMP"]) {
-					[rowValue setString:@"CURRENT_TIMESTAMP"];
-				} else if ([[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"typegrouping"] isEqualToString:@"bit"]) {
-					[rowValue setString:[NSString stringWithFormat:@"b'%@'", ((![[rowObject description] length] || [[rowObject description] isEqualToString:@"0"]) ? @"0" : [rowObject description])]];
-				} else if ([[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"typegrouping"] isEqualToString:@"date"]
-							&& [[rowObject description] isEqualToString:@"NOW()"]) {
-					[rowValue setString:@"NOW()"];
+					fieldValue = @"CURRENT_TIMESTAMP";
+				} else if ([fieldTypeGroup isEqualToString:@"bit"]) {
+					fieldValue = [NSString stringWithFormat:@"b'%@'", ((![[rowObject description] length] || [[rowObject description] isEqualToString:@"0"]) ? @"0" : [rowObject description])];
+				} else if ([fieldTypeGroup isEqualToString:@"date"] && [[rowObject description] isEqualToString:@"NOW()"]) {
+					fieldValue = @"NOW()";
 				} else {
-					[rowValue setString:[NSString stringWithFormat:@"'%@'", [mySQLConnection prepareString:[rowObject description]]]];
+					fieldValue = [NSString stringWithFormat:@"'%@'", [mySQLConnection prepareString:[rowObject description]]];
 				}
 			}
 		}
-		[fieldValues addObject:[NSString stringWithString:rowValue]];
+
+		// If the field value hasn't changed (only occurs while editing!), continue without saving
+		if (!fieldValueHasChanged) continue;
+
+		// Store the key and value in the ordered arrays for saving.
+		[rowFieldsToSave addObject:[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"name"]];
+		[rowValuesToSave addObject:fieldValue];
 	}
 
-	// Use INSERT syntax when creating new rows - no need to do not loaded checking, as all values have been entered
-	if ( isEditingNewRow ) {
+	[[NSNotificationCenter defaultCenter] postNotificationOnMainThreadWithName:@"SMySQLQueryWillBePerformed" object:tableDocumentInstance];
+	NSMutableString *queryString;
+
+	// Use INSERT syntax when creating new rows
+	if (isEditingNewRow) {
 		queryString = [NSString stringWithFormat:@"INSERT INTO %@ (%@) VALUES (%@)",
-					   [selectedTable backtickQuotedString], [[tableDataInstance columnNames] componentsJoinedAndBacktickQuoted], [fieldValues componentsJoinedByString:@","]];
-	// Use UPDATE syntax otherwise
+					   [selectedTable backtickQuotedString], [rowFieldsToSave componentsJoinedAndBacktickQuoted], [rowValuesToSave componentsJoinedByString:@", "]];
+
+	// Otherwise use an UPDATE syntax to save only the changed cells - if this point is reached,
+	// the equality test has failed and so there is always at least one changed cell
 	} else {
-		BOOL firstCellOutput = NO;
 		queryString = [NSMutableString stringWithFormat:@"UPDATE %@ SET ", [selectedTable backtickQuotedString]];
-		for ( i = 0 ; i < [dataColumns count] ; i++ ) {
-
-			// If data column loading is deferred and the value is the not loaded string, skip this cell
-			if (prefsLoadBlobsAsNeeded && [[fieldValues objectAtIndex:i] isSPNotLoaded]) continue;
-
-			if (firstCellOutput) [queryString appendString:@", "];
-			else firstCellOutput = YES;
-
+		for (i = 0; i < [rowFieldsToSave count]; i++) {
+			if (i) [queryString appendString:@", "];
 			[queryString appendFormat:@"%@ = %@",
-									   [[NSArrayObjectAtIndex(dataColumns, i) objectForKey:@"name"] backtickQuotedString], [fieldValues objectAtIndex:i]];
+									   [NSArrayObjectAtIndex(rowFieldsToSave, i) backtickQuotedString],
+									   NSArrayObjectAtIndex(rowValuesToSave, i)];
 		}
 		[queryString appendFormat:@" WHERE %@", [self argumentForRow:-2]];
 	}
 
+	[rowFieldsToSave release];
+	[rowValuesToSave release];
+
+	// Run the query
 	[mySQLConnection queryString:queryString];
 
-	[fieldValues release];
 	[[NSNotificationCenter defaultCenter] postNotificationOnMainThreadWithName:@"SMySQLQueryHasBeenPerformed" object:tableDocumentInstance];
 
 	// If no rows have been changed, show error if appropriate.
@@ -2494,7 +2503,7 @@
 		isEditingRow = NO;
 		isEditingNewRow = NO;
 		currentlyEditingRow = -1;
-		[[SPQueryController sharedQueryController] showErrorInConsole:[NSString stringWithFormat:NSLocalizedString(@"/* WARNING %@ No rows have been affected */\n", @"warning shown in the console when no rows have been affected after writing to the db"), currentTime] connection:[tableDocumentInstance name]];
+		[[SPQueryController sharedQueryController] showErrorInConsole:NSLocalizedString(@"/* WARNING: No rows have been affected */\n", @"warning shown in the console when no rows have been affected after writing to the db") connection:[tableDocumentInstance name]];
 		return YES;
 
 	// On success...
@@ -2582,7 +2591,7 @@
 	isSavingRow = YES;
 
 	// Attempt to save the row, and return YES if the save succeeded.
-	if ([self addRowToDB]) {
+	if ([self saveRowToTable]) {
 		isSavingRow = NO;
 		return YES;
 	}