Accpac and SQL Server
I blogged about Accpac and its databases here. This was a general article about how Accpac works with the various databases it supports. This article is more specific to Microsoft SQL Server and covers various topics that affect Accpac using SQL Server for its databases. I’ll be specifically talking about SQL Server 2008, but most of what I say applies equally to SQL Server 2005. Generally SQL Server is quite a reliable and low maintenance database server that doesn’t require much in the way of configuration and administration. Accpac uses SQL Server in a fairly straight forward manner issuing standard SQL statements without using SQL Server specific modules. This means Accpac runs on all editions of SQL Server, since we don’t use features only available in higher editions, and it means we can work with most of SQL Server’s built in services and configurations. We store the database in an open manner, following standard practices, which allows you to access your Accpac data using standard SQL aware tools including most reporting solutions. I also blogged on business continuity here, which is related to the topics discussed in this article.
Setup – Collation
One of the first decisions you need to make is a database collation sequence. This defines the character set used in the database as well as the sort order for the database. Generally choose the one that is best for your location and the language you use. However there are a couple of notes to consider:
Most western character set names either end in _BIN or _CI_AS such as Latin1_General_BIN or SQL_Latin1_General_CP1_CI_AS. The _BIN means that this is a binary sort order where strings will be sorted using a computer binary order, the upshot is that A-Z are before a-z and things like accented characters will be at the end. The CI_AS ones are case insensitive and will be sorted in dictionary order meaning AaBb… and accented characters are inserted in with their base letter. A few consequences of this for Accpac are:
- If you are migrating from Pervasive.SQL, then since Pervasive uses a binary sort order, if you choose a _BIN sort order, there shouldn’t be any problems. If you choose a _CI_ one in SQL Server then since this is case insensitive, you will get record already exists errors if you load a database that has key fields that only vary by case. Typically this happens in unit of measures ilke Ea, EA, ea. If you want to make this conversion you will need to fix up your Pervasive database before DB-Dumping.
- If you chose a _CI_ sort order then since strings are case insensitive, when you do searches, say from the finder, then it doesn’t matter the case you enter, so searching for steve would return Steve, STEVE or steve. This is the main reason people want to use this sort order.
- If you want to change the sort order, you will need to DBDump create a new database in the new sort order and DBLoad, however you could get problems with the keys and need to make some manual adjustments based on the errors returned.
Setup – Configuration
At a minimum, you want to have TCP/IP and Shared Memory enabled as protocols. TCP/IP is required for the new Sage ERP Accpac 6.0A Portal, and is the network protocol that works best for the rest of Accpac. Shared Memory is a very high performance protocol that will be used if the program using SQL Server is running on the same computer as the SQL Server service, basically bypassing the whole network stack. The main gotcha here is SQL Server express which will have TCP/IP disabled and will further be configured to not receive external requests (connections tab of the server properties in the management studio). This is configured from the SQL Server Configuration Manager:
If you right click on the TCP/IP protocol, choose properties and then select the second tab, you can see the network port being used by SQL Server.
If you are running multiple instances of SQL Server, then you can enter the servername\instancename in Database Setup, however you can’t do this in the portal configuration. In the portal configuration you must you the server name and the correct port number. Each instance of SQL Server will be using a unique port number.
When Accpac first supported SQL Server we only supported access by a pre-setup ODBC data source. This led to problems with people setting these up incorrectly, since there are quite a few settings that were possible. Then later on we allowed you to connect by just specifying the server name (or servername\instancename) in database setup. Then we would correctly setup an ODBC data source for you (usually servername32). This then worked far more reliably. We left the ODBC option there so people already setup this way wouldn’t be affected, or if there was some reason that special configuration values were required, you could still set them. I don’t know of any such special configuration values, not do I know of any good reason to use an ODBC data source rather than the server name. So I would strongly recommend you always use the server name in Database Setup to configure your SQL Server companies.
Database Dump and Load
DBDump and DBLoad are two utilities that come with Accpac that allow you to easily dump databases into a database independent format and reload them. These allow you to easily move Accpac companies between locations or between different database servers. I blogged on these previously here. These are very handy utilities and have some interesting side effects like re-indexing and compacting databases (since they completely re-create and reload the database). However they aren’t as fast as the built in SQL Server backup and restore facilities.
64 Bit SQL Server
Although Sage ERP Accpac is a 32-bit application, it works just fine with the 64-bit version of SQL Server. You cannot directly load 32-bit DLLs into a 64-bit application, but this isn’t how SQL Server works. Accpac (or any other program) is never loaded into SQL Server’s process space. All communications is between two processes using a standard well defined protocol, so it doesn’t matter whether either is 32 or 64 bits. Generally you want to run the 64-version of SQL Server on a 64-Bit version of Windows Server 2008. This way you can get better performance by adding more memory (the 32-Bit versions don’t really use memory beyond 4gig).
One caveat is that the ODBC data sources used by Accpac are 32 bit ones and stored in the 32-bit part of the registry. To see them you have to use the 32-bit version of odbcad32.exe which you need to run from the strange location of: C:\Windows\SysWOW64\ODBCAD32.exe.
If you are running in a standard workstation setup client/server configuration then each workstation communicates with SQL Server over the network. For best performance you want as good network connectivity as you can get, but generally a 100 Megabit connection is fine.
If you are running using Citrix or Terminal Server then if the SQL Server is also on the Terminal/Citrix server then it can use shared memory access which provides good performance. However this is tempered by how much memory and processor resources are required by the Accpac Business Logic, UIs and SQL Server. Generally once you get past a few users then it works better to separate the SQL Server over to a separate machine with a high speed connection to the Citrix/Terminal server, ideally having them both on a gigabit backbone. As we move to the Web, a Web Server will replace the Citrix/Terminal server and then the same advice would apply for the Web Server.
Another recommendation I’ve heard is to ensure you only use switches and not hubs and to beware that if you are using VOIP that you aren’t saturating your network bandwidth with phone traffic.
I know a lot of people that swear by various DAS (Direct Attached Storage), NAS (Network Attached Storage) and SAN (Storage Area Network) solutions. But my own experience has been a bit negative with these. I find them very useful for storing large amounts of files, like virtual images, photos and such. But I find them un-reliable and often with performance problems when using them to store databases being directly accessed by a database server. There are also now cloud services to have your database in the cloud and your application server on premise, but I tend to be skeptical of the performance and uptime of such services. However these all make great backup devices.
My own preference is to use RAID storage on the server. RAID 0 is the fastest, but doesn’t have redundancy (and so never recommend this). Then the other RAID levels offer various levels of redundancy, so if a drive fails, it can be replaced without losing any data. Have a look at the link: http://en.wikipedia.org/wiki/RAID. The decision of which to go with depends a bit on how much redundancy you want to how much you are willing to pay. RAID 5 is very redundant, but tends to suffer a bit in performance.
A recommendation we often give is to locate your LDF files to RAID 1 storage and your MDF and other IDX files to RAID 1+0 storage.
Even with the reliability of RAID, make sure you still backup your company databases whether mirroring to offsite servers, backing up to rotating external hard drives, DBDumping, etc. Also remember it’s a good idea to test that you can restore your backups. Remember that the value of your company database far exceeds the value of the equipment it is stored on.
SQL Server supports a number of database mirroring options; meaning that you can have your SQL Server stream database changes to a mirror SQL Server. Besides acting as a hot standby in case of failure, you can use this as a reporting server. Often reporting through Crystal can put a fairly big strain on the SQL Server, and one way offload this is to configure users that only do read-only access via reporting to connect to the mirror server. This way a department that runs many reports won’t impact the main data entry that is going on.
These are just a few tips and tricks for dealing with Accpac and SQL Server. Generally as your database becomes larger and the number of users increases, so does the amount of care you need to take of your database and network infrastructure; but, for smaller installations generally you just need to ensure you take regular backups. Of course if you don’t want to deal with database administration at all, then you might want to consider using a cloud service like AccpacOnline.