Questions tagged [etl]
'Extract, Transform and Load': Data load processing, normally in the context of data warehouse systems.
205
questions
1
vote
0answers
56 views
Parallel insert and delete into staging tables
I work on a small system that receives quite a lot of data from multiple sources (hundreds of them). Depending on few factors I can get anywhere from few rows to a couple of thousands (in fact ...
0
votes
0answers
25 views
Are temporary columns a good solution for loading data for a small scale data migration?
Our team is facing the following scenario. We're trying to import data from a denormalized data set in MySQL into a normalized MySQL database and are unsure of what a good solution would be for ...
0
votes
1answer
32 views
Transactional Replication data during rebuild
To offload reporting I have transactional replication running between my prod box and my reporting server (top image #1). This works great until the snapshot has to be rebuilt. During this time users/...
0
votes
1answer
58 views
SSIS data flow gets stuck reading table with no errors
When I'm doing ETL in SSIS, the data flow task "pauses" reading from the source transactional Live IO DB (the one on the left). It stops reading the data and "pauses" on random rows and then does ...
0
votes
3answers
76 views
Window Function to get pairs of records and compute the time difference
I'm working with an event dataset as the one in the example below:
Event_Type Event_Timestamp Is_Active
A 2010-10-01 00:00:00 1
B 2010-10-01 00:00:01 1
A ...
1
vote
1answer
18 views
Is it faster to truncate destination and copy all source data or lookup and keep only non-matching data with SSIS transfer packages?
I am building an Azure SQL DB database and to do this I will have to regularly (weekly-monthly) pull data from various other servers. I am designing SSIS packages to do this and whilst most of the ...
2
votes
1answer
217 views
Linked server returned message “Query timeout expired.”
We have two separate SQL Servers. On one server we have a data warehouse (DWH), on the other we have sales information database.
Now on the DWH server there is an ETL job that collects the ...
1
vote
1answer
34 views
SSIS comparison load between new, updated and deleted records and populate a staging database
So far,
My control flow looks like:
Execute SQL Task
- This executes a statement that creates a staging table. If one exists, it is dropped so everytime the package is run, the staging table will be ...
0
votes
1answer
44 views
What do I need to develop an integration service to extract data from an Oracle DB to a SQL Server DB using Visual Studio 2015? [closed]
I have to develop an ETL to extract some data from an Oracle DB 11g to a SQL Server 2017 DB. I am pretty new at all this technology so I would like some advices. The strongest problem so far is to ...
3
votes
3answers
172 views
How to handle schema changes in source systems when running an ETL?
How do people typically handle schema changes in source systems when running an ETL as part of an EDW? For example when a column you were operating on disappears and your ETL breaks.
3
votes
0answers
31 views
Migrating Access Saved Import Specifications to SSIS Package
We currently receive a multi-hundred column flat file from a vendor, and the tech prior to me had created an import specification in Microsoft Access to automatically split the file into the right ...
0
votes
0answers
20 views
ETL from non public database to a public one
I have a database that is in a private network. The database is not publicly accessible (you have to be on the local network to access it). We would like to use an ETL tool like FiveTran to export the ...
0
votes
2answers
86 views
Can Transactional Replication and triggers be used for near-realtime ETL [closed]
We want to have a data warehouse synced with our production OLTP database in near realtime. Is it possible to do this with Transactional Replication and triggers?
How we currently ETL
We use sql ...
2
votes
1answer
89 views
ETL, Production, Development — Should these be different servers? Instances?
You can say I've become an "accidental DBA" as people have left this company and I'm managing many aspects of the BI system now suddenly.
My predecessor left quite the mess regardless but I'm trying ...
0
votes
0answers
33 views
How to Represent a VARCHAR Column with XML Data in a Fact Table?
I have SQL Server 2016 environment and I have decided to design a source table with holds some sort of event data as a transactional fact table. The table has about a million rows, and generates about ...
29
votes
4answers
851 views
What is a scalable way to simulate HASHBYTES using a SQL CLR scalar function?
As part of our ETL process, we compare rows from staging against the reporting database to figure out if any of the columns have actually changed since the data was last loaded.
The comparison is ...
1
vote
1answer
73 views
When to Disable and Recreate Indexes in Data Warehouse ETL?
We are moving data from Staging Database into Kimball Data Warehouse DB.
I am hearing different ideas regarding when to disable and rebuild indexes.
Stage tables are truncated every day for each new ...
-2
votes
1answer
111 views
Datawarehouse Staging Tables: Null or Not Null
We are loading data from OLTP into Staging Tables with SSIS, then into Kimball data warehouse with ETL process.
We are inquiring about staging tables, if they should have null/not null constraints. ...
3
votes
2answers
133 views
Structured .TXT Data To A Proper DBMS [closed]
I'm presented with multiple .txt documents (each with its own set of columns) containing rows separated by some type of delimiter (which is different across the files). Each .txt file has different ...
0
votes
1answer
320 views
Query or ETL process to insert data into fact tables in SSMS
I'm working on creating a star schema for my project. I want to use it for reporting. I have used Google Play Store dataset from Kaggle.
The thing that I'm having trouble loading data into my fact ...
1
vote
0answers
66 views
Increase frequency of updates (ETL process) to Data Warehouse
Our data warehouse is updated only once every 24 hours (at night). The ETL process takes a little over an hour to complete. I am wondering how to increase the frequency of the ETL process - so running ...
6
votes
2answers
489 views
SQL Staging Tables: Primary Key Clustered or Heap
We are taking legacy flat txt files and inserting them into stage tables with SSIS.The question arose whether table should have primary clustered key index or not. This is direct flat file import with ...
0
votes
1answer
65 views
SSIS Installation on Dedicated Server
We are planning on installing SSIS 2016 on a new dedicated ETL server.
The packages will be called from SQL Server Agent (on a separate server), or from an application (again on a separate server).
...
0
votes
1answer
56 views
What's your data ETL methodology? [closed]
I think this is more like an open question: How do you do the ETL for your company?
We are using MySQL as our database management system and we have a production schema. Every month, when we received ...
2
votes
1answer
673 views
Efficiently bulk upsert unrelated rows
As part of a manual replication process between databases with different but related schemas, for each table, we identify new and modified records in the source database and feed them via a table ...
1
vote
1answer
182 views
How to copy selected table data from sql server to mysql on a daily basis? [closed]
I am having a retail pos application with MSSQL database. Now I need to transfer selected table data from SQL server to MYSQL database on a daily basis like job.
How to achive this?
0
votes
2answers
367 views
SSIS ETL or CDC - real time DWH reporting
I am currently working on SSIS package for continuous incremental data loads of the tables (40 tables now and expected to increase in near future) from OLTP system to a Reporting database residing on ...
1
vote
1answer
1k views
SQL Fastest Way to find Data Difference Between Two Tables
I am trying to locate fastest way to find difference between two tables. The first table is populated from text files daily, the second table is maintained in our database. We need to add data that ...
1
vote
1answer
125 views
reseed auto_increment to specific number?
Is it possible to set the identity column of a table to start from a specific value?
I'm converting an ETL stage from mysql to a sql server database where a staging database loads records with a ...
-2
votes
1answer
73 views
Can ETL access Data while Rebuild Index Operation is running
Can I get some help to understand below questions:
We have a ETL job running (Datawarehouse Server) and weekly index operations (Production Server)(Ola Hallengren script) , below questions are ...
1
vote
2answers
62 views
How do I run a stored procedure only on newest data loaded?
My database has a table where the data is loaded from an Excel upload. Then, a stored procedure is run on the data to validate it and insert it to another table.
Currently, my stored procedure will ...
2
votes
1answer
122 views
Handling variable fields in a CSV file with JSON?
Im trying to figure out the engineering to get a CSV file into PostgreSQL.
Requirements:
The CSV has X number of predetermined required fields
The CSV file has Y number of dynamic fields
Example:
...
2
votes
1answer
53 views
Is it bad practice to use a data-warehouse for providing reorganized non-BI data?
The Primary goal is the case-optimized data representation. The idea is to gather data from several databases, save the data in a data-warehouse and restructure/connect the data in data marts(similar ...
0
votes
1answer
367 views
SQL Bulk import vs SSIS in Simplicity
We are deciding between bulk insert or SSIS. We have a simple spreadsheet with 5 columns, customerid, cost, date, product name, etc. The spreadsheet is generally only around 200 rows every week.
All ...
2
votes
1answer
2k views
Is it impossible to force MariaDB users to SSL?
First of all, my english is really bad, so sorry for my english mistakes.
I have a MariaDB 10.2.15. I installed SSL, and its working fine, but I cant force use SSL to users.
my.cnf:
[mysqld]
ssl
ssl-...
2
votes
0answers
39 views
SSIS - dynamically merging a group of files
I'm trying to create an import package for our new mssql database and I'm having to merge a group of 20 files together to be fed into a table on the database. However not all of those 20 files will be ...
0
votes
1answer
190 views
Multiple Agent Jobs Running same SSIS Package
I have the following doubt, is there a possibility to have faild a Job when are running simultaneously as the following example:
4 SQL Agent Jobs running the same SSIS in different schedules, I've ...
2
votes
2answers
2k views
Character Conversion Issue Importing From CSV File
After doing a load of CSV files, there are various words that are "written" to the database incorrectly.
Some examples:
Diã¡ria should be Diária
Crã©dito should be Crédito
Ligaã§ãµes should be ...
3
votes
1answer
6k views
Login failed for user 'NT AUTHORITY\ANONYMOUS LOGON' for SSIS
I have a SSIS package which is perform data migration between MySQL database and SQL server database. When I manually run it from visual studio or from SQL Server Management Studio, it ran ...
1
vote
0answers
92 views
SSISDB too large
I have client whose SSISDB is too large (71GB). I have tried to set RETENTION_WINDOW to 50 from 365 and ran the maintenance job, but it has made little difference. Can someone please suggest an ...
0
votes
0answers
92 views
Data warehousing (ETL): Scheduled data migration from MySQL to PostgreSQL
I've been assigned task of data warehousing for Reporting and data analysis. Let me first explain what we are going to do.
Step 1. Replicate production server MySQL database.
Step 2. Scheduled ETL: ...
0
votes
1answer
379 views
Load New Foreign Key in Facts Table, When Update Dimension with SCD Type 2
I'm working on the production of a Data Warehouse with SSIS, and today we create the first dimension with SCD of type 2. The fact table is linked in the DIM_CIPESSOA dimension through the idcipessoa ...
0
votes
0answers
216 views
Confusion in Informix when selecting dates with JOIN
I am trying to run a query in Informix, doing a join in a table of logs where we save the record of insertion of the rows.
Notice that the query below brings two results, with different insertion ...
4
votes
1answer
167 views
Single User Mode and Replication
If I put a replicated database in single user mode will the Log Agent count as the single user?
ALTER DATABASE [DatabaseName] SET SINGLE_USER WITH ROLLBACK IMMEDIATE
I'm trying to block users from ...
1
vote
1answer
277 views
Copying large amounts of data to another target tables
I'm migrating large amounts of data +40m of rows to a new version of the tables, my question would be more like, what could be the best way to improve the performance in terms of logging and execution ...
0
votes
1answer
311 views
Data Warehouse: Staging Area, DWH databases and ETL tool on one server? [closed]
I am thinking about a DWH server layout and I'd like to ask you if you can spot any downsides to this layout. The basic idea is to have Staging Area & Data Warehouse DBs and the ETL Tool for the ...
1
vote
2answers
136 views
Approaches for handling nvarchar sources to data warehouse
Situation is this...our data warehouse doesn't need nvarchar and is built using all non-unicode datatypes. But all new source systems are all coming in with unicode (utf8 Oracle or nvarchar in ...
-3
votes
1answer
391 views
I need to generate a GUID,help [closed]
I need help with an SSIS package, I need to generate a GUID code every time I register a row of data, can someone explain how it is done?
In the SISS package, the data is extracted from an excel file,...
0
votes
1answer
131 views
Restoring MSSQL back-ups to Oracle 12c
I currently have an Oracle 12c DW that has several data sources of varying types (MSSQL, Oracle, MS Access, PostgreSQL, etc.) being moved into it as part of our existing ETL process. We have FME (...
2
votes
1answer
40 views
How can I SELECT an 'instance' in PostgreSQL?
I am reading a paper called "Real Time Delta Extraction Based on Triggers to Support Data Warehousing" from the IEEE and they proposed the following code:
CREATE TRIGGER cdc_table ON db.table AS
...
