I have the following problem.
I have a special column in my tables (a blob). In order to read and write to that column, I need to call an SQL function on its value - to convert to a string when I read, and to convert from a string to this blob when I write.
The read part is easy - I can use a formula to run the sql function against the column. But formulas are read only. Using IUserType also did not seem to assist - I can get the blob and write my own code to convert it to my own type, but I don't want to do that - I already have a database function that does this work for me.
Any ideas?
You can specify sql to insert and update, see the reference documentation, "Custom SQL for create, update and delete". Here is an example from Ayende which uses stored procedures (which is not the same, just to see how it works).
Or you could write a database trigger which does this transformation.
Related
I have to save a PDF-File into a BLOB-Column from a Oracle DB.
I can't use Java and have to use an INSERT-Statement.
The only solutions I've found while searching were very complex.
Is there an easy solution like: INSERT INTO (BLOB_COLUMN) VALUES(BLOBPDF("myPDF.pdf") or something like that?
I would suggest that you use a stored procedure in Oracle where you pass the path to your PDF file and calling the stored procedure does the insert.
Look at the last two sample example here.
If the load is "one-shot" you can use SQLDeveloper.
Otherwise you can use sqlloader (http://docs.oracle.com/cd/B19306_01/server.102/b14215/ldr_params.htm) that is designed for this type of operations
While this seems like a basic problem, I've been ripping my hair out FOR DAYS trying to get an efficient solution to this.
I have a lookup table of values on a server that I read from and assemble into a string using a C# Script task. I write this string into a variable that I want to pass in as my WHERE parameters inside a large SQL query on a ADO.NET data source (from a different server which I only have read access to) in my data flow. For example, this string would just be something like
('Frank', 'John', 'Markus', 'Tom')
and I would append that as my WHERE clause.
I can't read from a variable directly for an ADO.NET data source AND I can't use the 'Expression' property to set my SQL either as my SQL query is over 4000 characters. I could use an Execute SQL Task to run my query, load the results into a recordset and I assume, then loop through the recordset but that's extremely inefficient.
What would be the best way to do this? My end goal is to put these results inside a table on the first server.
You could try to set up Script Component as source - variables and strings inside scripts can be longer than 4000 characters so you can fit your query inside.
Setup your component similar to this article: http://beyondrelational.com/modules/2/blogs/106/posts/11119/script-componentsource-part1.aspx
In this one you have example how to fetch data using ExecuteReader and put it to output of script component: http://beyondrelational.com/modules/2/blogs/106/posts/11124/ssis-script-component-as-source-adonet.aspx In this one you have instructions how to aquire connection properly: http://www.toadworld.com/platforms/sql-server/b/weblog/archive/2011/05/30/use-connections-properly-in-an-ssis-script-task
By joining this pieces of information you should be able to write your source Script Component which can fetch data using any length dynamically constructed query.
Good luck :)
You can do a simple select statement to return a list of values that will include ('Frank', 'John', 'Markus', 'Tom'). So your select would return :
Name
----------
Frank
John
Markus
Tom
Then, in SSIS, use a Merge Join Component (that will act as a INNER JOIN) instead of a where clause in your main query.
This is the cleaniest way to achieve what you want.
Within a stored procedure, I need to take a whole CSV file as a string, then pick out all the values in one "column" to do a further query on the database.
I cannot use a saved doc - so i think that rules out openrowset, and the whole thing has to be done within a stored procedure.
Have spent hours googling and trying, but can find a good answer. One possible was http://www.tainyan.com/articles/entry-32/converting-csv-to-sql-data-table-with-stored-procedure.html but it doesnt work and i can find the error.
How should this be done please?
I don't really like this but it will work, provided your csv column remains at the same column index. I'd be wary of the performance of this but it might work.
See Fiddle here: http://sqlfiddle.com/#!3/336b7/1
Basically convert your csv file to xml, cast to an xml type, then perform queries on the xml.
What is the best, most preferable (and, if possible, efficient) way to pass an array of strings from a .NET application to a SQL Server 2005 stored procedure?
1) Pass the array of strings as a comma- or semicolon-delimited string and parse it into a temporary table?
2) Pass the array as XML and use SQL Server 2005 methods to parse it into a temporary table?
3) Write an ancilliary stored procedure to deal with each string individually and having .NET calling it for every element in the array?
4) Other... What?
I would say solution 2) is the most elegant one, but it is certainly not the most efficient... Is it?
Read this article.
Arrays and Lists in SQL Server 2005
The other related articles:
Arrays and Lists in SQL Server
Edit:
Sorry I did not realized that it is already mentioned in comments.
It depends upon your requirements.
In case I am importing then pass the XML and use SQL Server 2005 methods to parse it into a temporary table
If the records are not in bulk, I can use semicolon-delimited string.
If it is like you have some enumeration values like filtering the records on the basis of multiple status then I can use In
Good and Bad points about array passing
Hope this will help you. :)
I have a program (flex) that queries a database and gets back a dataset (value, timestamp). In the program I then put each value in the set through an algorithm to get a new value resulting in all the values being transformed. Instead of having to do this transformation of data in my program I would like mysql to do it and send the results back. Essentially, I would like to do a SELECT statement that returns a modified dataset.
Assuming the computation can only be done in a stored procedure or function, yes - as long as you are using MySQL 5.0+. I recommend reading this article on MySQL stored procedures & functions.