I'm very new to SSIS, but have this week been completely burried in turorials of how to use it, this has been very fruitful so far but now I'm stuck with what seems a more complicated task.
I have two source SQl tables, which are dynamically created using the TSQL pivot function - so the numebr of columns in each will vary.
I feed a list of criteria into a for each loop whic his set to use an ADO enumerator to go through this data set and has a script task to set the string variable SQL_DOWNLOAD_STRING to point to one of the two poential tables using an IF statement. TABLEA or TABLEB.
I tried using the standard OLE DB source in the data flow, but the associated meta data was generated based on TABLEA at the time of build. I then set the SQL statement to be based on the variable SQL_DOWNLOAD_STRING and when I execute, the meta data of the source has changed as obviously it is a differnt table. That said even if itwas the same table there is no guarentee that the columns would be the same.
So my question is - how do I create the OLE DB Source dynamically so that it reconfigures to the new structure of the table?
Then I'm trying to export the data to an Excel workbook (which again I can do for a static source) but in this instance the mapping would need to change too & I imagine I'll need to rebuild the destination table to match the source from above.
If I can get a working example - then finishing the project should be pretty staright forward from there - examples for this sort of thing seem pretty limited though :(
Please help! (PS I'm working in VB)
Thanks
Related
Problem:
I need to get data sets from CSV files into SQL Server Express (SSMS v17.6) as efficiently as possible. The data sets update daily into the same CSV files on my local hard drive. Currently using MS Access 2010 (v14.0) as a middleman to aggregate the CSV files into linked tables.
Using the solutions below, the data transfers perfectly into SQL Server and does exactly what I want. But I cannot figure out how to refresh/update/sync the data at the end of each day with the newly added CSV data without having to re-import the entire data set each time.
Solutions:
Upsizing Wizard in MS Access - This works best in transferring all the tables perfectly to SQL Server databases. I cannot figure out how to update the tables though without deleting and repeating the same steps each day. None of the solutions or links that I have tried have panned out.
SQL Server Import/Export Wizard - This works fine also in getting the data over to SSMS one time. But I also cannot figure out how to update/sync this data with the new tables. Another issue is that choosing Microsoft Access as the data source through this method requires a .mdb file. The latest MS Access file formats are .accdb files so I have to save the database in an older .mdb version in order to export it to SQL Server.
Constraints:
I have no loyalty towards MS Access. I really am just looking for the most efficient way to get these CSV files consistently into a format where I can perform SQL queries on them. From all I have read, MS Access seems like the best way to do that.
I also have limited coding knowledge so more advanced VBA/C++ solutions will probably go over my head.
TLDR:
Trying to get several different daily updating local CSV files into a program where I can run SQL queries on them without having to do a full delete and re-import each day. Currently using MS Access 2010 to SQL Server Express (SSMS v17.6) which fulfills my needs, but does not update daily with the new data without re-importing everything.
Thank you!
You can use a staging table strategy to solve this problem.
When it's time to perform the daily update, import all of the data into one or more staging tables. Execute SQL statement to insert rows that exist in the imported data but not in the base data into the base data; similarly, delete rows from the base data that don't exist in the imported data; similarly, update base data rows that have changed values in the imported data.
Use your data dependencies to determine in which order tables should be modified.
I would run all deletes first, then inserts, and finally all updates.
This should be a fun challenge!
EDIT
You said:
I need to get data sets from CSV files into SQL Server Express (SSMS
v17.6) as efficiently as possible.
The most efficient way to put data into SQL Server tables is using SQL Bulk Copy. This can be implemented from the command line, an SSIS job, or through ADO.Net via any .Net language.
You state:
But I cannot figure out how to refresh/update/sync the data at the end
of each day with the newly added CSV data without having to re-import
the entire data set each time.
It seems you have two choices:
Toss the old data and replace it with the new data
Modify the old data so that it comes into alignment with the new data
In order to do number 1 above, you'd simply replace all the existing data with the new data, which you've already said you don't want to do, or at least you don't think you can do this efficiently. In order to do number 2 above, you have to compare the old data with the new data. In order to compare two sets of data, both sets of data have to be accessible wherever the comparison is to take place. So, you could perform the comparison in SQL Server, but the new data will need to be loaded into the database for comparison purposes. You can then purge the staging table after the process completes.
In thinking further about your issue, it seems the underlying issue is:
I really am just looking for the most efficient way to get these CSV
files consistently into a format where I can perform SQL queries on
them.
There exist applications built specifically to allow you to query this type of data.
You may want to have a look at Log Parser Lizard or Splunk. These are great tools for querying and digging into data hidden inside flat data files.
An Append Query is able to incrementally add additional new records to an existing table. However the question is whether your starting point data set (CSV) is just new records or whether that data set includes records already in the table.
This is a classic dilemma that needs to be managed in the Append Query set up.
If the CSV includes prior records - then you have to establish the 'new records' data sub set inside the CSV and append just those. For instance if you have a sequencing field then you can use a > logic from the existing table max. If that is not there then one would need to do a NOT compare of the table data with the csv data to identify which csv records are not already in the table.
You state you seek something 'more efficient' - but in truth there is nothing more efficient than a wholesale delete of all records and write of all records. Most of the time one can't do that - but if you can I would just stick with it.
I was wondering if someone could help me with creating a while loop to iterate through multiple databases(100 databases) and drop/Truncate the tables(Around 60 tables in each database) within those databases.Thank you.
My task is to create an SSIS package to move the data from source database to target database.Data in the destination needs to be truncated as part of the process whenever I run that package the old data need to be truncated and the new data needs to be inserted.
Kindly help.
Thank you.
I am just explain how i would go about this problem.
Hoping the destination and source database,tables are of similar schema.
1) Try to create a table with all the database (Source and destination) details all 60 in a separate database.
2) You need get the database details using execute SQL task from the table and use For Each container for looping the logic of truncate the destination table and then move the data from source database to destination (The data is moved from source database one after other).
3) You will need to use Dynamic SQL and stored procedures for moving the data from source database to destination database (That you must be knowing). or You can use Data flow task too if you don't want to use Stored procedure or Dynamic Queries.
Hope it helps you! :)
Using SSIS at run-time how do you create a destination table in SQL Server (with the right number of fields, names, data types etc.) solely based off a source table structure from Oracle? The reason for asking is my Oracle tables often changes structure (fields added, data types changed etc.) and my package breaks if there is a mismatch say between the number of source and destination table fields. I need to automate this as I am scheduling packages to run as jobs in SSMS. I have looked everywhere and tried everything but cannot find a suitable solution to this problem....however I'm sure it is possible...somehow.
I'm using SSIS to import data from one DB to another existing DB. Some columns in the destination tables do not exist in the source tables. Seems the Import & Export Wizard only allows me to select unmapped columns from the source and match them with these new columns in the destination. I'd like to be able to just provide one piece of data to import into all rows of these new columns.
Would like to use the GUI if possible because I'm not skilled at writing scripts. Thanks!
In SSIS, you can add a "derived column" component that will add columns to the buffer rows with the value you want (either a string or an expression).
I don't believe this is possible in the GUI. However, it would be a simple script after the data is loaded with SSIS:
UPDATE table SET newcolumn = new value
If you need to filter the rows, just add
WHERE column = value ...
You could change your source to a select query and list out the columns along with the static value you want to map.
SELECT SOURCECOLUMN_1,SOURCECOLUMN_2,....,SOURCECOLUMN_N,'VALUE' AS DESTINATIONCOLUMN FROM Source_Table
My original thought was that you could use the query right in the Import & Export wizard. you can obviously do alot more if you go in and edit the package, but it sounded like you didn't have much expereince with that. Here is how you would do this in the wizard.
After you have selected your source and destination databases you can Specify Table Copy or Query. Select the Write a query to specify the data to transfer option
On the next screen enter the query listing out all of the columns and add in your static columns.
On the Next screen You will need to select the Destination table or it will default to creating a new table named Query. You should be able to choose from the drop down. As long as you aliased your extra columns with the same names it should map correctly. You can go in and edit mappings here if needed.
You can then save off the SSIS package and it will source form the query.
Alternatively if you already have the SSIS pacakge created without the extra columns you can go in to the Data Flow and change the Data access mode in the OLE DB Source to be a SQL Command instead of a table or view. Add your query here.
You can then go into the properties of the OLE DB Desitination in the Dataflow and map the new column. You could also add in a derived column as #DominicGoulet by adding in a Dervied Column task and putting your static information here and then mapping. If you want to see that solution too let me know.
I am currently using a database that is poorly designed and a slow pipeline so i decided to copy a small portion of the database (15 tables) and only bring over some of those tables for example i want to bring only the rows that have a certain id.
But this is not a one time move i need to add all the stuff that is added to the old database added to the new one on an hourly basis. My research has led me to SSIS and that it may have a way of accomplishing this but i have found no clear examples on how it is done if in fact it is possible. Thanks in advance.
Yes it is possible . You can schedule your ssis package through sql agent to run on hourly basis .
For a table ,you can drag a Data Flow Task on to the control flow .Inside DFT ,you need to place an oledb Source component ,Lookup ,Data conversion (if the types are different in source and target table) and Oledb destination .
oledb Source component : Create a variable of type string and in the expression write your sql query to fetch the data based on ID.Now use this variable in source component.
Lookup: You need to select your source table and combine the primary key column from the source and destination table.It acts similar to inner join query .After combining the primary key from the both the tables ,select the columns which you need from the source .
Oledb destination : Simply select your target table and map the columns from Lookup no matched output .If you need to update the values from the source then use Lookup matched output and connect it to an execute SQL task and write the update query .
Please go thru the link and SO
Scheduling of SSIS package