I am working on a project where I need to programmatically validate and/or compare a database schema between product releases.
I am using Perl and am looking for a cross-platform method to collect the database schema. I am currently able to perform database queries by utilizing the dbisql.exe command and then parsing the results.
I am wondering if there is potentially a stored procedure or set of queries that I can run to collect the database schema.
It appears that the dbunload.exe command could be used to generate a SQL regeneration script however I am thinking that this output may be difficult to parse.
Any feedback would be greatly appreciated.
If you would like to retrieve the DB schema data on a really low level you could query the corresponding system tables. They are in the SYS-Namespace, especially SYSTABLE (for all tables) and SYSCOLUMN for all fields in those tables.
Check the ASA SQL Reference Handbook for the schema of those system tables.
With Perl's DBI you can easily fire queries on those tables. But you will have to create some local storage for the schema to compare the query results with.
Sybase Central v3.0 has the possibility to export DDL with all DB objects;
and I think SC v6.0 can't connect to ASA 11 :(
Related
We recently migrated a large DB2 database to a new server. It got trimmed a lot in the migration, for instance 10 years of data chopped down to 3, to name a few. But now I find that I need certain data from the old server until after tax season.
How can I run a UNION query in DBeaver that pulls data from two different connections..? What's the proper syntax of the table identifiers in the FROM and JOIN keywords..?
I use DBeaver for my regular SQL work, and I cannot determine how to span a UNION query across two different connections. However, I also use Microsoft Access, and I easily did it there with two Pass-Through queries that are fed to a native Microsoft Access union query.
But how to do it in DBeaver..? I can't understand how to use two connections at the same time.
For instance, here are my connections:
And I need something like this...
SELECT *
FROM ASP7.F_CERTOB.LDHIST
UNION
SELECT *
FROM OLD.VIPDTAB.LDHIST
...but I get the following error, to which I say "No kidding! That's what I want!", lol... =-)
SQL Error [56023]: [SQL0512] Statement references objects in multiple databases.
How can this be done..?
This is not a feature of DBeaver. DBeaver can only access the data that the DB gives it, and this is restricted to a single connection at a time (save for import/export operations). This feature is being considered for development, so keep an eye out for this answer to be outdated sometime in 2019.
You can export data from your OLD database and import it into ASP7 using DBeaver (although vendor tools for this are typically more efficient for this). Then you can do your union as suggested.
Many RDBMS offer a way to logically access foreign databases as if they were local, in which case DBeaver would then be able to access the data from the OLD database (as far as DBeaver is concerned in this situation, all the data is coming from a single connection). In Postgres, for example, one can use a foreign data wrapper to access foreign data.
I'm not familiar with DB2, but a quick Google search suggests that you can set up foreign connections within DB2 using nicknames or three-part-names.
If you check this github issue:
https://github.com/dbeaver/dbeaver/issues/3605
The way to solve this is to create a task and execute it in different connections:
https://github.com/dbeaver/dbeaver/issues/3605#issuecomment-590405154
Is it possible to get the table structure like db2look from SQL?
Or the only way is from command line? Thus, by wrapping a external stored procedure in C I could call the db2look, but that is not what I am looking for.
Clarification added later:
I want to know which tables have the non logged option from SQL.
It is possible to create the table structure from regular SQL and the public DB2 catalog - however, it is complex and requires some deeper skills.
The metadata is available in the DB2 catalog views in the SYSCAT schema. For a regular table you would first start off by looking into the values in SYSCAT.TABLES and SYSCAT.COLUMNS. From there you would need to branch off to other views depending on what table and column options you are after, whether time-travel tables, special partitioning rules, or many other options are involved.
Serge Rielau published an article on developerWorks called Backup and restore SQL schemas for DB2 Universal Database that provides a set of stored procedures that will do exactly what you're looking for.
The article is quite old (2006) so you may need to put some time in to update the procedures to be able to handle features that were added to DB2 since the date of publication, but the procedures may work for you now and are a nice jumping off point.
As part of some requirement, I need to migrate a schema from some existing database to a new schema in a different database. Some part of it is already done and now I need to compare the 2 schema and make changes in the new schema as per gap finding.
I am not using a tool and was trying to understand some details using syscat command but could not get much success.
Any pointer on what is the best way to solve this?
Regards,
Ramakant
A tool really is the best way to solve this – IBM Data Studio is free and can compare schemas between databases.
Assuming you are using DB2 for Linux/UNIX/Windows, you can do a rudimentary compare by looking at selected columns in SYSCAT.TABLES and SYSCAT.COLUMNS (for table definitions), and SYSCAT.INDEXES (for indexes). Exporting this data to files and using diff may be the easiest method. However, doing this for more complex structures (tables with range or database partitioning, foreign keys, etc) will become very complex very quickly as this information is spread across a lot of different system catalog tables.
An alternative method would be to extract DDL using the db2look utility. However, you can't specify the order that db2look outputs objects (db2look extracts DDL based on the objects' CREATE_TIME), so you can't extract DDL for an entire schema into a file and expect to use diff to compare. You would need to extract DDL into a separate file for each table.
Use SchemaCrawler for IBM DB2, a free open-source tool that is designed to produce text output that is designed to be diffed. You can get very detailed information about your schema, including view and stored procedure definitions. All of the information that you need will be output in a single file, and can be compared very easily using a standard diff tool.
Sualeh Fatehi, SchemaCrawler
unfortunately as per company policy, cannot use these tools at this point of time. So am writing some program using JDBC to get the details and do some comparison kind of stuff.
I want to transfer some tables of DB2 to oracle daily for accessing them from web page,
But I don't know commands of DB2. How to do this?
I want this action should perform on database daily on particular time, so is there any tool is available to do this operation. And for writing the program for operating above query which programming language should I use? I am using windows XP.
I think Change Data Capture is used to replicate DML from one database to other databases continuously.
However, what you need is to transfer some data at a particular time each day, thus CDC could be too heavy for that.
You could do a simply "db2 export", and then you could import the generated file from Oracle.
There should be an option to create an adapter in Oracle that permits to query DB2 tables. The opposite is called federation in DB2 (InfoSphere Information Server) that permits to query Oracle tables.
Export http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/topic/com.ibm.db2.luw.admin.cmd.doc/doc/r0008303.html
CMD examples http://publib.boulder.ibm.com/infocenter/db2luw/v9r7/topic/com.ibm.db2.luw.admin.dm.doc/doc/r0004567.html
Check this link
http://blogs.oracle.com/warehousebuilder/entry/simple_change_data_capture_from_db2_table_to_oracle_table
In 11.2 releases, Change Data Capture (CDC) can be done by code template mapping. This allows users to capture the data changes from heterogeneous data source, and load into the target across different platforms.
Is there a way to query an Information Schema from DB2 and dump the contents(tables - structure only),into another database? I'm looking for a way to create a shell model of a database schema from DB2 into a SQL Server database?
Thanks
You can use db2look to get the table structure (DDL) out of db2.
Once you've got it, however, I'm afraid you'll have to manually replace any db2-specific syntax (datatypes, storage parameters, etc.) with it's corresponding SQL Server syntax.
It doesn't look like Microsoft's Migration Tool works for db2 yet. :(