According to the Features that are not support in SQL Database, TEXTPTR and UPDATETEXT aren't supported in Azure's SQL Database. Is there another way that can be used to insert/update big text/image fields, so that we can avoid having the entire column contents in memory?
UPDATETEXT is depricated since SQL Server 2005. You should use UPDATE ... SET ... .WRITE instead.
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My ssis package has an oledb source which joins oracle and sql server to get source data and loads it into sql server oledb destination. Earlier we were using linked server for this purpose but we cannot use linked server anymore.
So I am taking the data from sql server and want to return it to the in clause of the oracle query which i am keeping as sql command oledb source.
I tried parsing an object type variable from sql server and putting it into the in clause of oracle query in oledb source but i get error that oracle cannot have more than 1000 literals in the in statement. So basically I think I have to do something like this:
select * from oracle.db where id in (select id from sqlserver.db).
Since I cannot use linked server so i was thinking if I could have a temp table which can be used throughout the package.
I tried out another way of using merge join in ssis. but my source data set is really large and the merge join is returning fewer rows than expecetd. I am badly stuck at this point. I have tried a number if things nothung seems to be working.
Can someone please help. Any help will be greatly appreciated.
A couple of options to try.
Lookup:
My first instinct was a Lookup Task, but that might not be a great solution depending on the size of your data sets, since all of the records from both tables have to pulled over the wire and stored in memory on the SSIS server. But if you were able to pull off a Merge Join, then a Lookup should also work, but it might be slow.
Set an OLE DB Source to pull the Oracle data, without the WHERE clause.
Set a Lookup to pull the id column from your SQL Server table.
On the General tab of the Lookup, under Specify how to handle rows with no matching entries, select Redirect rows to no-match output.
The output of the Lookup will just be the Oracle rows that found a matching row in your SQL Server query.
Working Table on the Oracle server
If you have the option of creating a table in the Oracle database, you could create a Data Flow Task to pipe the results of your SQL Server query into a working table on the Oracle box. Then, in a subsequent Data Flow, just construct your Oracle query to use that working table as a filter.
Probably follow that up with an Execute SQL Task to truncate that working table.
Although this requires write access to Oracle, it has the advantage of off-loading the heavy lifting of the query to the database machine, and only pulling the rows you care about over the wire.
I am working on writing a Spring Java program accessing data from Athena, but I found that Athena JDBC driver does not support PreparedStatement, does anyone have idea about how to avoid SQL injection on Athena?
Update: I originally answered this question in 2018, and since then Athena now supports query parameters.
Below is my original answer:
You'll have to format your SQL query as a string before you prepare the query, and include variables by string concatenation.
In other words, welcome to PHP programming circa 2005! :-(
This puts the responsibility on you and your application code to ensure the variables are safe, and don't cause SQL injection vulnerabilities.
For example, you can cast variables to numeric data types before you interpolate them into your SQL.
Or you can create an allowlist when it's possible to declare a limited set of values that may be allowed. If you accept input, check it against the whitelist. If the input is not in the allowlist, don't use it as part of your SQL statement.
I recommend you give feedback to the AWS Athena project and ask them when they will provide support for SQL query parameters in their JDBC driver. Email them at Athena-feedback#amazon.com
See also this related question: AWS Athena JDBC PreparedStatement
Athena now has support for prepared statements (this was not the case when the question was asked).
That being said, prepared statements aren't the only way to guard against SQL injection attacks in Athena, and SQL injection attacks aren't as serious as they are in a database.
Athena is just a query engine, not a database. While dropping a table can be disruptive, tables are just metadata, and the data is not dropped along with it.
Athena's API does not allow multiple statements in the same execution, so you can't sneak a DROP TABLE foo into a statement without completely replacing the query.
Athena does not, by design, have any capability of deleting data. Athena has features that can create new data, such as CTAS, but it will refuse to write into an existing location and cannot overwrite existing data.
I am trying to load data from falt file source to Sybase IQ 15.1 destination using SSIS 2008. I am using ADO.NET destination component with Sybase IQ ODBC data provider to connect to the Sybase IQ db. Though the package is able to load the data, performance of the package is extremely slow. Its just loading 150 rows per minute. I am executing the package through SQL Server Agent. There are no data transformations in the package.
Can any one please tell me how can i improve the performance?
Thanks in advance
ODBC drivers are generally slow. How many columns are you pulling in? Also, have you checked your buffer sizes and stuff?
Use BulkInsertWheneverPossible property to true, it will improve the performance.
To access that property right click->ADO.NET destination-> choose properties or ShowAdvanceEditor
(MSDN Reference)
http://technet.microsoft.com/en-us/library/ms135971(v=sql.105).aspx#adonet
A value that specifies whether to use the System.Data.SqlClient.SqlBulkCopy interface to improve the performance of bulk insert operations. Only certain ADO.NET providers support this interface.
The default value is True.
In T-SQL (Microsoft SQL 2008), how can I make a new database which will have the same schemas, tables, table columns, indexes, constraints, and foreign keys, but will not contain any data from the original database?
Note: making a full copy, then removing all data is not a solution in my case, since the database is quite big, and such full copy will spend too much time.
See here for instructions: How To Script Out The Whole Database In SQL Server 2005 and SQL Server 2008
In SQL Management Studio, right click on the database and select "Script database as"
http://msdn.microsoft.com/en-us/library/ms178078.aspx
You can then use the script to create an empty one.
Edit : OP did say 2008
I use liquibase for this purpose. Just point liquibase to a different server and it will use your changelog to bring the second database up to date, schema wise. It has the added benefit that the changelog file gets stored in source control and so I can have tagged versions of it, allowing me to restore a database to what a specific version of my app is expecting.
We have some data in the SQL server table that needs to scramble. Some data are string and some data are date.
What is best way to do this?
Are you talking about Obfuscating your SQL Server Data? (To create a development version based on the production data without exposing the production data itself)
Or do you want it encrypted?
SQL Server 2005 introduced encryption support. Check out this article here.