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  • Documentation and Test Assertions in Databases

    - by Phil Factor
    When I first worked with Sybase/SQL Server, we thought our databases were impressively large but they were, by today’s standards, pathetically small. We had one script to build the whole database. Every script I ever read was richly annotated; it was more like reading a document. Every table had a comment block, and every line would be commented too. At the end of each routine (e.g. procedure) was a quick integration test, or series of test assertions, to check that nothing in the build was broken. We simply ran the build script, stored in the Version Control System, and it pulled everything together in a logical sequence that not only created the database objects but pulled in the static data. This worked fine at the scale we had. The advantage was that one could, by reading the source code, reach a rapid understanding of how the database worked and how one could interface with it. The problem was that it was a system that meant that only one developer at the time could work on the database. It was very easy for a developer to execute accidentally the entire build script rather than the selected section on which he or she was working, thereby cleansing the database of everyone else’s work-in-progress and data. It soon became the fashion to work at the object level, so that programmers could check out individual views, tables, functions, constraints and rules and work on them independently. It was then that I noticed the trend to generate the source for the VCS retrospectively from the development server. Tables were worst affected. You can, of course, add or delete a table’s columns and constraints retrospectively, which means that the existing source no longer represents the current object. If, after your development work, you generate the source from the live table, then you get no block or line comments, and the source script is sprinkled with silly square-brackets and other confetti, thereby rendering it visually indigestible. Routines, too, were affected. In our system, every routine had a directly attached string of unit-tests. A retro-generated routine has no unit-tests or test assertions. Yes, one can still commit our test code to the VCS but it’s a separate module and teams end up running the whole suite of tests for every individual change, rather than just the tests for that routine, which doesn’t scale for database testing. With Extended properties, one can get the best of both worlds, and even use them to put blame, praise or annotations into your VCS. It requires a lot of work, though, particularly the script to generate the table. The problem is that there are no conventional names beyond ‘MS_Description’ for the special use of extended properties. This makes it difficult to do splendid things such ensuring the integrity of the build by running a suite of tests that are actually stored in extended properties within the database and therefore the VCS. We have lost the readability of database source code over the years, and largely jettisoned the use of test assertions as part of the database build. This is not unexpected in view of the increasing complexity of the structure of databases and number of programmers working on them. There must, surely, be a way of getting them back, but I sometimes wonder if I’m one of very few who miss them.

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  • Can I get a dump of all my databases *except one* using mysqldump?

    - by Daniel Magliola
    I'm currently using mySQLdump to backup my dev machine and servers. There is one project I just started, however, that has a HUUUUUGE database that I don't really need backed up, and i'll be a big problem to add it to the rest of the backup cycle. I'm currently doing this: "c:\Program Files\mysql\MySQL Server 5.1\bin\mysqldump" -u root -pxxxxxx --all-databases g:\backups\MySQL\mysqlbackup.sql Is it possible to somehow specify "except this database(s)"? I wouldn't like to have to specify the list of DBs manually, since that would mean that I'd have to remember updating my backup batch file every time I create a new DB, and I know that's not gonna happen. EDIT: As you probably guessed from my command line above, i'm doing this on Windows, so I can't do any kind of fancy bash stuff, only wimpy .bat things. Alternatively, if you have other ideas to solve this same issue, they are more than welcome, of course! Thanks Daniel

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  • Migrating SQL Server Databases – The DBA’s Checklist (Part 2)

    - by Sadequl Hussain
    Continuing from Part 1  , our Migration Checklist continues: Step 5: Update statistics It is always a good idea to update the statistics of the database that you have just installed or migrated. To do this, run the following command against the target database: sp_updatestats The sp_updatestats system stored procedure runs the UPDATE STATISTICS command against every user and system table in the database.  However, a word of caution: running the sp_updatestats against a database with a compatibility level below 90 (SQL Server 2005) will reset the automatic UPDATE STATISTICS settings for every index and statistics of every table in the database. You may therefore want to change the compatibility mode before you run the command. Another thing you should remember to do is to ensure the new database has its AUTO_CREATE_STATISTICS and AUTO_UPDATE_STATISTICS properties set to ON. You can do so using the ALTER DATABASE command or from the SSMS. Step 6: Set database options You may have to change the state of a database after it has been restored. If the database was changed to single-user or read-only mode before backup, the restored copy will also retain these settings. This may not be an issue when you are manually restoring from Enterprise Manager or the Management Studio since you can change the properties. However, this is something to be mindful of if the restore process is invoked by an automated job or script and the database needs to be written to immediately after restore. You may want to check the database’s status programmatically in such cases. Another important option you may want to set for the newly restored / attached database is PAGE_VERIFY. This option specifies how you want SQL Server to ensure the physical integrity of the data. It is a new option from SQL Server 2005 and can have three values: CHECKSUM (default for SQL Server 2005 and latter databases), TORN_PAGE_DETECTION (default when restoring a pre-SQL Server 2005 database) or NONE. Torn page detection was itself an option for SQL Server 2000 databases. From SQL Server 2005, when PAGE_VERIFY is set to CHECKSUM, the database engine calculates the checksum for a page’s contents and writes it to the page header before storing it in disk. When the page is read from the disk, the checksum is computed again and compared with the checksum stored in the header.  Torn page detection works much like the same way in that it stores a bit in the page header for every 512 byte sector. When data is read from the page, the torn page bits stored in the header is compared with the respective sector contents. When PAGE_VERIFY is set to NONE, SQL Server does not perform any checking, even if torn page data or checksums are present in the page header.  This may not be something you would want to set unless there is a very specific reason.  Microsoft suggests using the CHECKSUM page verify option as this offers more protection. Step 7: Map database users to logins A common database migration issue is related to user access. Windows and SQL Server native logins that existed in the source instance and had access to the database may not be present in the destination. Even if the logins exist in the destination, the mapping between the user accounts and the logins will not be automatic. You can use a special system stored procedure called sp_change_users_login to address these situations. The procedure needs to be run against the newly attached or restored database and can accept four parameters. Depending on what you want to do, you may be using less than four though. The first parameter, @Action, can take three values. When you specify @Action = ‘Report’, the system will provide you with a list of database users which are not mapped to any login. If you want to map a database user to an existing SQL Server login, the value for @Action will be ‘Update_One’. In this case, you will only need to provide the database user name and the login it will map to. So if your newly restored database has a user account called “bob” and there is already a SQL Server login with the same name and you want to map the user to the login, you will execute a query like the following: sp_change_users_login         @Action = ‘Update_One’,         @UserNamePattern = ‘bob’,         @LoginName = ‘bob’ If the login does not exist, you can instruct SQL Server to create the login with the same name. In this case you will need to provide a password for the login and the value of the @Action parameter will be ‘Auto_Fix’. If the login already exists, it will be automatically mapped to the user account. Unfortunately sp_change_users_login system stored procedure cannot be used to map database users to trusted logins (Windows accounts) in SQL Server. You will need to follow a manual process to re-map the database user accounts.  Continues…

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  • Oracle Magazine - OWB 11gR2 and Heterogeneous Databases

    - by David Allan
    There's a nice article titled 'Oracle Warehouse Builder 11g Release 2 and Heterogeneous Databases' from Oracle ACE director and cofounder of Rittman Mead Consulting, Mark Rittman in the May/June 2010 Oracle Magazine that covers the heterogeneous database support in OWB 11gR2: http://www.oracle.com/technology/oramag/oracle/10-may/o30bi.html Big thanks to Mark for this write up. There is an Oracle white paper on the support here and for examples of this extensibility you can go to the OWB blog archive where there are quite a few posts. I would recommend the following interesting posts out of the archive architecture overview, bulk file loading, MySQL open connectivity and MySQL bulk extract as interesting posts amongst others.

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  • TFS: Work Items values from External Databases

    - by javarg
    A common question in TFS forums is how to populate list items from external sources in Work Items. Well, there is not a specific functionality to integrate Work Items with external databases or systems when designing them. Actually, you will need to associate your Work Items fields with Global Lists and then have some automated process update this global list regularly. Download this ImportGlobalList.zip file. I’ve put together a simple class (TfsGlobalList) that you can use to update global list items from a .NET application. You could for example, create a simple Console App and schedule it using Windows Scheduler. This App would query a database and then update a TFS Global List using the provided code. Note: the provided code must be run under an account with modify Global List permissions in TFS. Note: remember to refresh Team Explorer in order to see updates in Work Item field values. Enjoy!  

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  • Automatizing the backup of my databases and files with cron

    - by Patrick
    hi, I want to automatize the backup of my databases and files with cron. Should I add the following lines to crontab ? mysqldump -u root -pPASSWORD database_name | gzip > /home/backup/database_`date +\%m-\%d-\%Y`.sql.gz svn commit -m "Committing the working copy containing the database dump" 1) First of all, is this a good approach? 2) It is not clear how to specify the repository and the working copy with svn. 3) How can I run svn only when the mysqldump is done and not before ? Avoiding conflicts Any other tip ? thanks

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  • No databases showing in phpMyAdmin

    - by Thein Hla Maw
    My website is hosted in shared hosting service and is working fine with updated news stored in MySQL database. To manage the database of website, I install phpMyAdmin in a sub-folder with the same username and password used in website. When I login to phpMyAdmin, I don't see my database. phpMyAdmin is showing "No databases" in left pane. Is there any thing I need to configure in phpMyAdmin? Edited: This is the settings in config.inc.php. I can login to phpMyAdmin successfully. $cfg['Servers'][$i]['host'] = 'hostname'; $cfg['Servers'][$i]['port'] = ''; $cfg['Servers'][$i]['socket'] = ''; $cfg['Servers'][$i]['connect_type'] = 'tcp'; $cfg['Servers'][$i]['extension'] = 'mysqli'; $cfg['Servers'][$i]['auth_type'] = 'cookie'; $cfg['Servers'][$i]['user'] = 'dbuser'; $cfg['Servers'][$i]['password'] = 'password';

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  • Good architecture for user information on separate databases?

    - by James P. Wright
    I need to write an API to connect to an existing SQL database. The API will be written in ASP.Net MVC3. The slight problem is that with existing users of the system, they may have a username on multiple databases. Each company using the product gets a brand new instance of the database, but over the years (the system has been running for 10 years) there are quite a few users (hundreds) who have multiple usernames across multiple "companies" (things got fragmented obviously and sometimes a single Company has 5 "projects" that each have their own database). Long story short, I need to be able to have a single unified user login that will allow existing users to access their information across all their projects. The only thing I can think is storing a bunch of connection strings, but that feels like a really bad idea. I'll have a new Database that will hold the "unified user" information...can anyone suggest a solid system architecture that can handle a setup like this?

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  • Alternatives to sql like databases

    - by user613326
    Well i was wondering these days computers usually have 2GB or 4GB memory I like to use some secure client server model, and well an sql database is likely candidate. On the other hand i only have about 8000 records, who will not frequently be read or written in total they would consume less then 16 Megabyte. And it made me wonder what would be good secure options in a windows environment to store the data work with it multi-client single server model, without using SQL or mysql Would for well such a small amount of data maybe other ideas better ? Because i like to keep maintenance as simple as possible (no administrators would need to know sql maintenance, as they dont know databases in my target environment) Maybe storing in xml files or.. something else. Just wonder how others would go if ease of administration is the main goal. Oh and it should be secure to, the client server data must be a bit secure (maybe NTLM files shares https or...etc)

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  • migrating sharepoint databases

    - by Alex Bransky
    If you're wondering how to migrate your SharePoint databases to a new server, this Microsoft article is actually pretty useful, though still overly complex like most of their other articles. http://technet.microsoft.com/en-us/library/cc512725.aspx The one thing I would change is that they seem to recommend installing SQL Server Configuration Manager on web servers, when all that was needed in my case was to add an entry to the hosts file on the SharePoint web server that used the IP address of the new SQL Server with the name of the old SQL Server.  This might not be appropriate in cases where the old server is not being decommissioned.

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  • Quickly Investigating What's in the Tables of SQL Server Databases

    From SQL Server Management Studio it's hard to look through the first few rows of a whole lot of tables in a database. This is odd, since it is a great way to get quickly familiar with a database. Phil tidied up a SQL routine he uses to investigate databases quickly in a browser. He explains how to use it, how it works, and how to use it from PowerShell. Want faster, smaller backups you can rely on?Use SQL Backup Pro for up to 95% compression, faster file transfer and integrated DBCC CHECKDB. Download a free trial now.

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  • Rebuilding system databases in 2008 R2

    - by TiborKaraszi
    All my attempts so far to rebuild the system databases in 2008 R2 has failed. I first tried to run setup from below path: C:\Program Files\Microsoft SQL Server\100\Setup Bootstrap\Release But above turns out to be the 2008 setup program, not 2008R2 setup; even though I have no 2008 instanced installed (I have only R2 instances installed). Apparently, the 2008 setup program does a version check of the instance to be rebuilt and since it is > 10.50.0, the rebuild fails. Books Online for R2 the section...(read more)

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  • SQL SERVER – Faster SQL Server Databases and Applications – Power and Control with SafePeak Caching Options

    - by Pinal Dave
    Update: This blog post is written based on the SafePeak, which is available for free download. Today, I’d like to examine more closely one of my preferred technologies for accelerating SQL Server databases, SafePeak. Safepeak’s software provides a variety of advanced data caching options, techniques and tools to accelerate the performance and scalability of SQL Server databases and applications. I’d like to look more closely at some of these options, as some of these capabilities could help you address lagging database and performance on your systems. To better understand the available options, it is best to start by understanding the difference between the usual “Basic Caching” vs. SafePeak’s “Dynamic Caching”. Basic Caching Basic Caching (or the stale and static cache) is an ability to put the results from a query into cache for a certain period of time. It is based on TTL, or Time-to-live, and is designed to stay in cache no matter what happens to the data. For example, although the actual data can be modified due to DML commands (update/insert/delete), the cache will still hold the same obsolete query data. Meaning that with the Basic Caching is really static / stale cache.  As you can tell, this approach has its limitations. Dynamic Caching Dynamic Caching (or the non-stale cache) is an ability to put the results from a query into cache while maintaining the cache transaction awareness looking for possible data modifications. The modifications can come as a result of: DML commands (update/insert/delete), indirect modifications due to triggers on other tables, executions of stored procedures with internal DML commands complex cases of stored procedures with multiple levels of internal stored procedures logic. When data modification commands arrive, the caching system identifies the related cache items and evicts them from cache immediately. In the dynamic caching option the TTL setting still exists, although its importance is reduced, since the main factor for cache invalidation (or cache eviction) become the actual data updates commands. Now that we have a basic understanding of the differences between “basic” and “dynamic” caching, let’s dive in deeper. SafePeak: A comprehensive and versatile caching platform SafePeak comes with a wide range of caching options. Some of SafePeak’s caching options are automated, while others require manual configuration. Together they provide a complete solution for IT and Data managers to reach excellent performance acceleration and application scalability for  a wide range of business cases and applications. Automated caching of SQL Queries: Fully/semi-automated caching of all “read” SQL queries, containing any types of data, including Blobs, XMLs, Texts as well as all other standard data types. SafePeak automatically analyzes the incoming queries, categorizes them into SQL Patterns, identifying directly and indirectly accessed tables, views, functions and stored procedures; Automated caching of Stored Procedures: Fully or semi-automated caching of all read” stored procedures, including procedures with complex sub-procedure logic as well as procedures with complex dynamic SQL code. All procedures are analyzed in advance by SafePeak’s  Metadata-Learning process, their SQL schemas are parsed – resulting with a full understanding of the underlying code, objects dependencies (tables, views, functions, sub-procedures) enabling automated or semi-automated (manually review and activate by a mouse-click) cache activation, with full understanding of the transaction logic for cache real-time invalidation; Transaction aware cache: Automated cache awareness for SQL transactions (SQL and in-procs); Dynamic SQL Caching: Procedures with dynamic SQL are pre-parsed, enabling easy cache configuration, eliminating SQL Server load for parsing time and delivering high response time value even in most complicated use-cases; Fully Automated Caching: SQL Patterns (including SQL queries and stored procedures) that are categorized by SafePeak as “read and deterministic” are automatically activated for caching; Semi-Automated Caching: SQL Patterns categorized as “Read and Non deterministic” are patterns of SQL queries and stored procedures that contain reference to non-deterministic functions, like getdate(). Such SQL Patterns are reviewed by the SafePeak administrator and in usually most of them are activated manually for caching (point and click activation); Fully Dynamic Caching: Automated detection of all dependent tables in each SQL Pattern, with automated real-time eviction of the relevant cache items in the event of “write” commands (a DML or a stored procedure) to one of relevant tables. A default setting; Semi Dynamic Caching: A manual cache configuration option enabling reducing the sensitivity of specific SQL Patterns to “write” commands to certain tables/views. An optimization technique relevant for cases when the query data is either known to be static (like archive order details), or when the application sensitivity to fresh data is not critical and can be stale for short period of time (gaining better performance and reduced load); Scheduled Cache Eviction: A manual cache configuration option enabling scheduling SQL Pattern cache eviction based on certain time(s) during a day. A very useful optimization technique when (for example) certain SQL Patterns can be cached but are time sensitive. Example: “select customers that today is their birthday”, an SQL with getdate() function, which can and should be cached, but the data stays relevant only until 00:00 (midnight); Parsing Exceptions Management: Stored procedures that were not fully parsed by SafePeak (due to too complex dynamic SQL or unfamiliar syntax), are signed as “Dynamic Objects” with highest transaction safety settings (such as: Full global cache eviction, DDL Check = lock cache and check for schema changes, and more). The SafePeak solution points the user to the Dynamic Objects that are important for cache effectiveness, provides easy configuration interface, allowing you to improve cache hits and reduce cache global evictions. Usually this is the first configuration in a deployment; Overriding Settings of Stored Procedures: Override the settings of stored procedures (or other object types) for cache optimization. For example, in case a stored procedure SP1 has an “insert” into table T1, it will not be allowed to be cached. However, it is possible that T1 is just a “logging or instrumentation” table left by developers. By overriding the settings a user can allow caching of the problematic stored procedure; Advanced Cache Warm-Up: Creating an XML-based list of queries and stored procedure (with lists of parameters) for periodically automated pre-fetching and caching. An advanced tool allowing you to handle more rare but very performance sensitive queries pre-fetch them into cache allowing high performance for users’ data access; Configuration Driven by Deep SQL Analytics: All SQL queries are continuously logged and analyzed, providing users with deep SQL Analytics and Performance Monitoring. Reduce troubleshooting from days to minutes with database objects and SQL Patterns heat-map. The performance driven configuration helps you to focus on the most important settings that bring you the highest performance gains. Use of SafePeak SQL Analytics allows continuous performance monitoring and analysis, easy identification of bottlenecks of both real-time and historical data; Cloud Ready: Available for instant deployment on Amazon Web Services (AWS). As you can see, there are many options to configure SafePeak’s SQL Server database and application acceleration caching technology to best fit a lot of situations. If you’re not familiar with their technology, they offer free-trial software you can download that comes with a free “help session” to help get you started. You can access the free trial here. Also, SafePeak is available to use on Amazon Cloud. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Performance, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • SQL Authority News – Download and Install Adventure Works 2014 Sample Databases

    - by Pinal Dave
    If you are using SQL Server there are good chances that you are familiar with AdventureWorks. AdventureWorks is a Sample Database shipped with SQL Server and it can be downloaded from CodePlex site. AdventureWorks have replaced Northwind and Pubs from the sample database in SQL Server 2005. The Microsoft team keeps updating the sample database as they release new versions. I use the AdventureWorks database for most of my example, as it is easy to use sample database which is accessible for most of the people out there. Every new version  of SQL Server should have its own Adventureworks database. The reason is that SQL Server comes up with new features with every version and most of the new features need a new dataset sample to demonstrate the capabilities of the features. This is the why every version of SQL Server has its own AdventureWorks database. SQL Server 2014 has many new features and to support that Microsoft has released new Advetureworks 2014 Sample Database. You can download Adventure Works 2014 Sample Databases from here. Here is a quick tutorial how one can install the AdventureWorks database on your server. Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

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  • More Tables or More Databases?

    - by BuckWoody
    I got an e-mail from someone that has an interesting situation. He has 15,000 customers, and he asks if he should have a database for their data per customer. Without a LOT more data it’s impossible to say, of course, but there are some general concepts to keep in mind. Whenever you’re segmenting data, it’s all about boundary choices. You have not only boundaries around how big the data will get, but things like how many objects (tables, stored procedures and so on) that will be involved, if there are any cross-sections of data (do they share location or product information) and – very important – what are the security requirements? From the answer to these types of questions, you now have the choice of making multiple tables in a single database, or using multiple databases. A database carries some overhead – it needs a certain amount of memory for locking and so on. But it has a very clean boundary – everything from objects to security can be kept apart. Having multiple users in the same database is possible as well, using things like a Schema. But keeping 15,000 schemas can be challenging as well. My recommendation in complex situations like this is similar to a post on decisions that I did earlier – I lay out the choices on a spreadsheet in rows, and then my requirements at the top in the columns. I  give each choice a number based on how well it meets each requirement. At the end, the highest number wins. And many times it’s a mix – perhaps this person could segment customers into larger regions or districts or products, in a database. Within that database might be multiple schemas for the customers. Of course, he needs to query across all customers, that becomes another requirement. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • CMS and Databases vs. DIY

    - by hozza
    I have been programming for many years now, primarily in PHP and the like and would consider myself an intermediate programmer. Some of my online projects have now gone global and very widely used, i am now in deep thought about scalability etc. All of my systems so far are written in PHP, no known database structure such as MySQL etc. Instead our databases use an 'operating system style' method of storing information, files and folders if you will. We also do not use any outside/third-party software or CMS, so far this has work out extremely well. Most people, when they hear about the way we do things, criticize and say that is an idiotic idea but normally after seeing our systems in more dept are converted to our way of doing things. Is it really that bad to not use a standard databasing systems and only using the one (slightly heavier than others) language of PHP? How well on the face of it will this kind of setup scale? N.B. Our systems include things such as account and user management, documentation development and task/project managing.

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  • More Tables or More Databases?

    - by BuckWoody
    I got an e-mail from someone that has an interesting situation. He has 15,000 customers, and he asks if he should have a database for their data per customer. Without a LOT more data it’s impossible to say, of course, but there are some general concepts to keep in mind. Whenever you’re segmenting data, it’s all about boundary choices. You have not only boundaries around how big the data will get, but things like how many objects (tables, stored procedures and so on) that will be involved, if there are any cross-sections of data (do they share location or product information) and – very important – what are the security requirements? From the answer to these types of questions, you now have the choice of making multiple tables in a single database, or using multiple databases. A database carries some overhead – it needs a certain amount of memory for locking and so on. But it has a very clean boundary – everything from objects to security can be kept apart. Having multiple users in the same database is possible as well, using things like a Schema. But keeping 15,000 schemas can be challenging as well. My recommendation in complex situations like this is similar to a post on decisions that I did earlier – I lay out the choices on a spreadsheet in rows, and then my requirements at the top in the columns. I  give each choice a number based on how well it meets each requirement. At the end, the highest number wins. And many times it’s a mix – perhaps this person could segment customers into larger regions or districts or products, in a database. Within that database might be multiple schemas for the customers. Of course, he needs to query across all customers, that becomes another requirement. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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  • Are document-oriented databases meant to replace relational databases?

    - by evolve
    Recently I've been working a little with MongoDB and I have to say I really like it. However it is a completely different type of database then I am used. I've noticed that it is most definitely better for certain types of data, however for heavily normalized databases it might not be the best choice. It appears to me however that it can completely take the place of just about any relational database you may have and in most cases perform better, which is mind boggling. This leads me to ask a few questions: Are document-oriented databases have been developed to be the next generation of databases and basically replace relational databases completely? Is it possible that projects would be better off using both a document-oriented database and a relational database side by side for various data which is better suited for one or the other? If document-oriented databases are not meant to replace relational databases, then does anyone have an example of a database structure which would absolutely be better off in a relational database (or vice-versa)?

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  • Designing binary operations(AND, OR, NOT) in graphs DB's like neo4j

    - by Nicholas
    I'm trying to create a recipe website using a graph database, specifically neo4j using spring-data-neo4j, to try and see what can be done in Graph Databases. My model so far is: (Chef)-[HAS_INGREDIENT]->(Ingredient) (Chef)-[HAS_VALUE]->(Value) (Ingredient)-[HAS_INGREDIENT_VALUE]->(Value) (Recipe)-[REQUIRES_INGREDIENT]->(Ingredient) (Recipe)-[REQUIRES_VALUE]->(Value) I have this set up so I can do things like have the "chef" enter ingredients they have on hand, and suggest recipes, as well as suggest recipes that are close matches, but missing one ingredient. Some recipes can get complex, utilizing AND, OR, and NOT type logic, something like (Milk AND (Butter OR spread OR (vegetable oil OR olive oil))) and I'm wondering if it would be sane to model this in a graph using a tree type representation? An example of what I was thinking is to create three "node" types of AND, OR, and NOT and have each of them connect to the nodes value underneath. How else might this be represented in a Graph Database or is my example above a decent representation?

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  • jMonkey Quest Database

    - by theJollySin
    I am building a game in jMonkey (Java) and I have so far only used default quest text. But now I need to start populating a lot of quests with text. My design requires A LOT of quests texts. What is the best way to build a database of quest texts in jMonkey? I don't have a lot of real experience with databases. Is there a database that integrates well with jMonkey? Here are the ideal properties I want in my database, in order of priority: Reasonably light learning curve Easy portability (in Java) to Windows, Linux, and Mac OSX Good interface with Java Good interface with jMonkey The ability to add properties to the quests: ID, level, gender, quest chain ID, etc. Or am I wrong in thinking I need to use some giant monster like SQL? I haven't been able to find much information on this, so are people using some non-database methods for storing things like quest text in jMonkey?

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  • How do I implement a score database in Android?

    - by Michael Seun Araromi
    I making a 2D game for Android using OpenGL-ES technology. It is a space shooting game where the player shoots enemy ships. I want to keep a track of score for the amount of enemy ships destroyed and a record of a local highscore. The score should be incremented whenever an enemy is destroyed. I also want a way of displaying both the current score and highscore on the game screen. I am not familiar with databases at all and I will appreciate a clear answer or a link to a good tutorial for my cause. Thanks.

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  • Databases and Beer

    - by Johnm
    It is a bit of a no-brainer: Include the word "beer" in a subject line of an e-mail or blog post title and you can be certain that it will be read. While there are times this practice might be a ploy to increase readership, it is not the case for this blog post. There is inspiration that can be drawn from other industries to which we, as database professionals, can apply in our industry. In this post I will highlight one of my favorite participants of the brewing industry. The Boston Beer Company started in the 1970s in Boston, Massachusetts. Others may be more familiar with this company through their Samuel Adams Boston Lager and other various seasonal beers. I am continually inspired by their commitment to mastery of the brewing process to which they evangelize frequently in their commercials. They also are continually in pursuit of pushing the boundaries of beer as we know it while working within traditional constraints. A recent example of this is their collaboration with Weihenstephan Brewery of Munich, Germany to produce the soon to be released Infinium beer. This beer, while brewed as an ale, is touted as something closer to something like Champaign - all while complying with the Reinheitsgebot. The Reinheitsgebot is also known as the "German Beer Purity Law" which was originated in 1516. This law states that beer is to consist of water, barley, hops and yeast. That's it. Quite a limiting constraint indeed. and yet, The Boston Beer Company pushed forward. Much like the process of brewing, the discipline of database design and architecture is one that is continually in process and driven by the pursuit of mastery. While we do not have purity laws to constrain us, we have many other types: best practices, company policies, government regulations, security and budgets. Through our fellow comrades, we discuss the challenges and constraints in which we operate. We boil down the principles and theories that define our profession. We reassemble these into something that is complementary to the business needs that we must fulfill. As a result, it is not uncommon to see something amazingly innovative in a small business who is pushing the boundaries of their database well beyond its intended state. It is equally common to see innovation in the use of features available in the more advanced features of databases that are found in large businesses. The tag line for The Boston Beer Company is: "Take Pride In Your Beer.", I would like to offer an alternative and say "Take Pride In Your Database." So, As you pour your next Boston Lager into a frosted glass, consider those who spend their lives mastering the craft of brewing and strive to interject their spirit into everything that you do as a database professional. Cheers!

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  • Alternatives for comparing data from different databases

    - by Alex
    I have two huge tables on separate databases. One of them has the information of all the SMS that passed through the company's servers while the other one has the information of the actual billing of those SMS. My job is to compare samples of both of these tables (for example, the records between 1 and 2 pm) to see if there are any differences: SMS that were sent but not charged to the user for whatever reason that may be happening. The columns I will be using to compare are the remitent's phone number and the exact date the SMS was sent. An issue here is that dates usually are the same on both sides, but in many cases differ by 1 or 2 seconds. I have, so far, two alternatives to do this: (PL/SQL) Create two tables where i'm going to temporarily store all the records of that 1hour sample. One for each of the main tables. Then, for each distinct phone number, select the time of every SMS sent from that phone from both my temporary tables and start comparing one by one using cursors. In this case, the procedure would be ran on the server where one of the sources is so the contents of the other one would be looked up using a dblink. (sqlplus + c++) Instead of storing the 1hour samples in new tables, output the query to a text file. I will have two text files, one for each source. Then, open the first file and load all of it's content on a hash_map (key-value) using c++, where the key will be the phone number and the value a list of times of SMS sent from that phone. Finally, open the second file, grab each line (in this format: numberX timeX), look for numberX's entry on the hash_map (wich will be a list of times) and then check if timeX is on that list. If it isn't, save it somewhere to finally store it on a "uncharged" table (this would also be the final step on case 1) My main concern is efficiency. These samples have about 2 million records on each source, so just grabbing one record on one side and looking it up on the other would not be possible. That's the reason I wanted to use hash_maps Which do you think is a better option?

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  • SSIS: Building SQL databases on-the-fly using concatenated SQL scripts

    - by DrJohn
    Over the years I have developed many techniques which help automate the whole SQL Server build process. In my current process, where I need to build entire OLAP data marts on-the-fly, I make regular use of a simple but very effective mechanism to concatenate all the SQL Scripts together from my SSMS (SQL Server Management Studio) projects. This proves invaluable because in two clicks I can redeploy an entire SQL Server database with all tables, views, stored procedures etc. Indeed, I can also use the concatenated SQL scripts with SSIS to build SQL Server databases on-the-fly. You may be surprised to learn that I often redeploy the database several times per day, or even several times per hour, during the development process. This is because the deployment errors are logged and you can quickly see where SQL Scripts have object dependency errors. For example, after changing a table structure you may have forgotten to change any related views. The deployment log immediately points out all the objects which failed to build so you can fix and redeploy the database very quickly. The alternative approach (i.e. doing changes in the database directly using the SSMS UI) would require you to check all dependent objects before making changes. The chances are that you will miss something and wonder why your app returns the wrong data – a common problem caused by changing a table without re-creating dependent views. Using SQL Projects in SSMS A great many developers fail to make use of SQL Projects in SSMS (SQL Server Management Studio). To me they are invaluable way of organizing your SQL Scripts. The screenshot below shows a typical SSMS solution made up of several projects – one project for tables, another for views etc. The key point is that the projects naturally fall into the right order in file system because of the project name. The number in the folder or file name ensures that the projects the SQL scripts are concatenated together in the order that they need to be executed. Hence the script filenames start with 100, 110 etc. Concatenating SQL Scripts To concatenate the SQL Scripts together into one file, I use notepad.exe to create a simple batch file (see example screenshot) which uses the TYPE command to write the content of the SQL Script files into a combined file. As the SQL Scripts are in several folders, I simply use several TYPE command multiple times and append the output together. If you are unfamiliar with batch files, you may not know that the angled bracket (>) means write output of the program into a file. Two angled brackets (>>) means append output of this program into a file. So the command-line DIR > filelist.txt would write the content of the DIR command into a file called filelist.txt. In the example shown above, the concatenated file is called SB_DDS.sql If, like me you place the concatenated file under source code control, then the source code control system will change the file's attribute to "read-only" which in turn would cause the TYPE command to fail. The ATTRIB command can be used to remove the read-only flag. Using SQLCmd to execute the concatenated file Now that the SQL Scripts are all in one big file, we can execute the script against a database using SQLCmd using another batch file as shown below: SQLCmd has numerous options, but the script shown above simply executes the SS_DDS.sql file against the SB_DDS_DB database on the local machine and logs the errors to a file called SB_DDS.log. So after executing the batch file you can simply check the error log to see if your database built without a hitch. If you have errors, then simply fix the source files, re-create the concatenated file and re-run the SQLCmd to rebuild the database. This two click operation allows you to quickly identify and fix errors in your entire database definition.Using SSIS to execute the concatenated file To execute the concatenated SQL script using SSIS, you simply drop an Execute SQL task into your package and set the database connection as normal and then select File Connection as the SQLSourceType (as shown below). Create a file connection to your concatenated SQL script and you are ready to go.   Tips and TricksAdd a new-line at end of every fileThe most common problem encountered with this approach is that the GO statement on the last line of one file is placed on the same line as the comment at the top of the next file by the TYPE command. The easy fix to this is to ensure all your files have a new-line at the end.Remove all USE database statementsThe SQLCmd identifies which database the script should be run against.  So you should remove all USE database commands from your scripts - otherwise you may get unintentional side effects!!Do the Create Database separatelyIf you are using SSIS to create the database as well as create the objects and populate the database, then invoke the CREATE DATABASE command against the master database using a separate package before calling the package that executes the concatenated SQL script.    

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