I'm about to start a project for my other half; the ability to search archaeological images based on certain criteria. The ability to search these criteria is right up my street, a database of images (or their file-paths) associated to some meta-data. The interface would allow searching of the meta-data, then display the matches with t...
How do websites like Digg, Del.icio.us, and StackOverflow implement tagging? I know this other question has an accepted answer of a many-to-many relation with a cross ref table. But how do the "big boys" do it? The same way? How is it scaling? ...
The table in question is part of a database that a vendor's software uses on our network. The table contains metadata about files. The schema of the table is as follows Metadata ResultID (PK, int, not null) MappedFieldname (char(50), not null) Fieldname (PK, char(50), not null) Fieldvalue (text, null) There is a clustered index ...
Hi, given my current position (lat,long) I want to quickly find the nearest neighbor in a points of interest problem. Thus I intend to use an R-Tree database, which allows for quick lookup. However, first the database must be populated - of course. Therefore, I need to determine the rectangular regions that covers the area, where each re...
Hi In recent years I was using MSSQL databases, and all unique records in tables has the ID column type of bigint (long). It is autoincrementing and generally - works fine. Currently I am observing people prefer to use GUIDs for record's identity. Does it make sense to swap bigint to guid for unique record id? I think it doesn't make...
Our application has a CustomerNumber field. We have hundreds of different people using the system (each has their own login and their own list of CustomerNumbers). An individual user might have at most 100,000 customers. Many have less than 100. Some people only put actual numbers into their customer number fields, while others use ...
I want to run an update query against a production database and as good little developer I am trying to make it as safe as possible. I am looking to do the following BEGIN TRANSACTION UPDATE table_x SET col_y = 'some_value' . . . IF (@@error <> 0) BEGIN ROLLBACK END ELSE BEGIN COMMIT END The above should work i...
Is it possible to configure multiple database servers (all hosting the same database) to execute a single query simultaneously? I'm not asking about executing queries using multiple CPUs simultaneously - I know this it possible. UPDATE What I mean is something like this: There are two 2 servers: Server1 and Server2 Both server host ...
I've been trying to specialize into the MS SQL server technologies, but my job has required me to understand more MySQL recently. Has any MS SQL DBA or developer had to do this, and if so, what were their biggest challenges? At the moment, for me: Lack of decent IDE No easy ETL tools like ssis ...
Hi! I use the following bit of code in my Django app: pictures = gallery.picture_set.annotate( score=models.Sum( 'picturevote__value' ) ).order_by( '-score' ) There is a table of galleries. In each of them are some pictures. When a user votes up or down a picture, a new row in 'picturevote' is inserted and connected to the picture. Th...
Is it better to extend my business database with the tables of the ASP.NET Membership Security model. Or should I have a different datastore where I only manage Identities and Roles... Basically 1 or 2 databases? ...
The first normal form says that row ordering should not matter. Does this mean that a table with date as part of the key is not 1NF? e.g. Consider a table of ticker prices where date/time is part of the PK. In this case, you get the last price by ordering the data by date and selecting the top 1 row. Does this mean that for to fulfill 1N...
Hello all, I am currently creating a small table in Oracle and am unsure of which data type to choose for a particular column. The column is labelled 'stay' and I would like it to contain only these values 'Short', 'Medium' and 'Long'. The end goal is to have these values in a drop down list within a form. Am I right in picking a data...
The first picture is my query. I need to obtain results in second picture. What to do? Which query do have to use? Select OrarioA, OrarioB, Max(IDOrario), (????)IDDettaglioOrarioA, (???)IDDettaglioOrarioB FROM TABLE GROUP BY OrarioA, OrarioB, ?????????????? I need respective IDDettaglioOrarioA, IDDettaglioOrarioB. How to complet...
I've got a program that exports data using a user-made .csv or .txt Microsoft Text Driver ODBC datasource. I create this datasource brand new in the ODBC Data Source Administrator, with a path to a directory shared by both the program and the DS. Then in the program I give it my datasource and it apparently wants the datasource to have a...
Hi all. Nowadays, I'm working on a database, with no "Relations, PKs and FKs", just raw data. I can say that database is just set of papers. When I asked about this, I had this; "Hide the Business". Also, one of my friends said, this always happens in "Large systems". In large systems, they are tyring to hide thier business through ra...
Hi There, I have a very funny problem on my application, I get an error as follow: System.ArgumentException: An OLE DB Provider was not specified in the ConnectionString. An example would be, 'Provider=SQLOLEDB;'. However, when I tried to speicify the provider on my connection as Provider=SQLOLEDB.1 or Provider=SQLOLEDB, then I get ano...
Moving from Oracle to PostgreSQL, what (preferably free/OSS) software/tools are available that replace Oracle Enterprise Manager? I'm aware of pgAdmin, as well as some tools bundled into EnterpriseDB's Postgres Plus AS, but am looking for more context and a better overview of the PostgreSQL ecosystem. Specifically I'm interested in tool...
If a column is null, does that affect the space used by the column? Is the space used fixed by the column definition? Does this vary from database to database. (I am mainly interestred in SQL Server 2000.) Clarification: The question relates not to what happens when the column is 'nullable' (This costs another bit as Kritsen & gbn point...
Basically I want to do a innerjoin on "datatable1" which is on the webserver cache to that of another "datatable2" stored in database. I have 2 ways for this 1. I can bring "datatable2" to webserver cache and write a join logic. However this will be very costly and is ruled out. 2. Send "datatable1" to database and do a inner join th...