What is the best way to transfer the data from SQL Server database on Windows to a PostgreSQL database on Linux?
The current SQL Server database there are about 500,000 rows per table, and about 80 tables all together.
Thanks!
I'm not familiar enough with sql-server to assert this is the best way, but if you just need the data, you could try using odbc and a foreign data wrapper:
http://wiki.postgresql.org/wiki/Foreign_data_wrappers
Related
Is there a way to copy for example one column from MS Access to SQL Server or just a part of the column? I need to copy some rows of one column to SQL Server table just a way I would do this in the MS Excel. There is a great tool for manipulating data for Oracle, named PL/SQL Developer but I haven't found something similar for SQL Server.
Using ETL tools you can achieve your result. If you need opensource ETL tool then you can go ahead with Pentaho PDI. It's free.
I'm trying to query my Hortonworks cluster Hive tables from SQL Server. My scenario below:
HDP 2.6, Ambari, HiveServer2
SQL Server 2016 Enterprise
Kerberos configuration for secure logins in HDP
I was reading about the PolyBase service in SQL Server 2016 and I suppose later versions. However, I realize that according to the documentation what this service is going to perform in SQL Server is a bridge to reach out my HDFS and recreate external tables based in this data source.
Otherwise what I'm expecting is query Hive objects like these would be SQL Server objects as well, such as a linked server.
Someone has an example or knows if this is possible within SQL Server and Hive?
Thanks so much
Hive acts more as a job compiler than a database. This means every SQL statement you are writing will be translated into a job for Hadoop, sent over to the cluster and become executed there. From the user perspective it looks like querying a table.
The already mentioned approach by reading the HDFS data source and re-create it in SQL Server is the correct one. Since both, Hive and database server are different technologies, something like a linked server seems to technically not possible for me.
Hive provides nowadays a JDBC interface which could be used to connect to it. But even with Hive JDBC, every query will end up as cluster job for distributed computing, running over the files in HDFS, create a result set and present that to you.
If you want to querying Hive from SQL server, you can download ODBC driver (Microsoft or Hortonsworks) and create a Data Source Name (DSN) for Hive. In Advanced option check Use Native Query. Then just create new linked server in the SQL server with the same name of datasource as Data Source Name in ODBC driver.
Write openquery something like:
select top 100 * from
openquery(HadoopLinkedServer,
'column1, column2 from databaseInHadoop.tableInHadoop')
I have an Oracle database and a SQL Server database. There is one table say Inventory which contains millions of rows in both database tables and it keeps growing.
I want to compare the Oracle table data with the SQL Server data to find out which records are missing in the SQL Server table on daily basis.
Which is best approach for this?
Create SSIS package.
Create Windows service.
I want to consume less resource to achieve this functionality which takes less time and less resource.
Eg : 18 millions records in oracle and 16/17 millions in SQL Server
This situation of two different database arise because two different application online and offline
EDIT : How about connecting SQL server from oracle through Oracle Gateway to SQL server to
1) Direct query to SQL server from Oracle to update missing record in SQL server for 1st time.
2) Create a trigger on Oracle which gets executed when record is deleted from Oracle and it insert deleted record in new oracle table.
3) Create SSIS package to map newly created oracle table with SQL server to update SQL server record.This way only few records have to process daily through SSIS.
What do you think of this approach ?
I would create an SSIS package and load the data from the Oracle table use a Data Flow / OLE DB Data Source. If you have SQL Enterprise, the Attunity Connectors are a bit faster.
Then I would load key from the SQL Server table into a Lookup transformation, where I would match the 2 sources on the key, and direct unmatched rows into a separate output.
Finally I would direct the unmatched rows output to a OLE DB Command, to update the SQL Server table.
This SSIS package will require a lot of memory, but as the matching is done in memory with minimal IO, it will probably outperform other solutions for speed. It will need enough free memory to cache all the keys from the SQL Server Table.
SSIS also has the advantage that it has lots of other transformation functions available if you need them later.
What you basically want to do is replication from Oracle to SQL Server.
You could do this in SSIS, A windows Service or indeed a multitude of platforms.
The real trick is using the correct design pattern.
There are two general design patterns
Snapshot Replication
You take all records from both systems and compare them somewhere (so far we have suggestions to compare in SSIS or compare on Oracle but not yet a suggestion to compare on SQL Server, although this is valid)
You are comparing 18 million records here so this is a lot of work
Differential replication
You record the changes in the publisher (i.e. Oracle) since the last replication then you apply those changes to the subscriber (i.e. SQL Server)
You can do this manually by implementing triggers and log tables on the Oracle side, then use a regular ETL process (SSIS, command line tools, text files, whatever), probably scheduled in SQL Agent to apply these to the SQL Server.
Or you could do this by using the out of the box replication capability to set up Oracle as a publisher and SQL as a subscriber: https://msdn.microsoft.com/en-us/library/ms151149(v=sql.105).aspx
You're going to have to try a few of these and see what works for you.
Given this objective:
I want to consume less resource to achieve this functionality which takes less time and less resource
transactional replication is far more efficient but complicated. For maintenance purposes, which platforms (.Net, SSIS, Python etc.) are you most comfortable with?
Other alternatives:
If you can use Oracle gateway for SQL Server then you do not need to transfer data and can make the query directly.
If you can't use Oracle gateway, you can use Pentaho data integration or another ETL tool to compare tables and get results. Is easy to use.
I think the best approach is using oracle gateway.Just follow the steps. I have similar type of experience.
Install and Configure Oracle Database Gateway for SQL Server.
https://docs.oracle.com/cd/B28359_01/gateways.111/b31042/installsql.htm
Now you can create a dblink from oracle to sql server.
Create a procedure which compare the missing records in oracle database and insert into sql server database.
For example, you can use this statement inside your procedure.
INSERT INTO "dbo"."sql_server_table"#dblink_name("column1","column2"...."column5")
VALUES
(
select column1,column2....column5 from oracle_table
minus
select "column1","column2"...."column5" from "dbo"."sql_server_table"#dblink_name
)
Create a scheduler which execute the procedure daily.
When both databases are online, missing records will be inserted to sql server. Otherwise the scheduler fail or you can execute the procedure manually.
It takes minimum resource.
I will suggest having a homemade ETL solution.
Schedule an oracle job to export source table data (on a daily
manner based on the application logic ) to plain CSV format.
Schedule a SQL-Server job (with acceptable delay from first oracle job) to read this CSV file and import it
to a medium table inside sql-servter using BULK INSERT.
Last part of the SQL-Server job will be reading medium table data
and do the logic(insert, update target table). I suggest having another table to store reports of this daily job result.
I'm running into a problem when accessing a SQL Server table from an Oracle setup via ODBC.
I can access 90% of the tables absolutely fine, but there's a few tables that have a name that's longer than 30 characters. Whenever I try to interact with the table (describes, selects, etc) Oracle throws an "identifier too long" error and gives up.
Is there a way to coax Oracle into playing nice with the SQL Server tables?
Assuming that we are talking about an Oracle database that has a database link created to a SQL Server database via Heterogeneous Services, you would need to write code using the DBMS_HS_PASSTHROUGH package to interact with the tables in question. You'd also need to use this package if you have tables where there are column names that are not valid Oracle identifiers.
I am replacing an Access application with a web app, but the client is using SQL Server 2000, and I am using SQL Server 2008.
So, I have the database redesigned, with foreign keys, but now I need to get the data on the client's system.
Part of the problem is that they have images that are over 32k, so osql failed as the command buffer filled up.
I should be able to use osql to import the new schema at least, and perhaps all of the data except for the images.
The Export wizard just wouldn't work, even though I tried the Native SQL Driver and the OLE DB Sql Driver.
Flat files seems like a bad choice, as I don't know if it can do the images.
So, what is a good way to copy a 330M database from 2008 -> 2000?
Not sure about performance or time needed, but you could always try a tool like
Red-Gate SQL Compare / SQL Data Compare
Apex SQL Diff / SQL Data Diff
These will allow you to compare both the schema of two databases, as well as the data, and allow you to create synchronization scripts, or synchronize online.
Marc
I set the image column to null, which reduced the size of the insert statements.
This enabled me to import the data into the target database.