I happened to do some moderating stuff with large database but I am not so experienced in it so i guess the smart thing is to create similar database on my localhost to not mess up with original one.And here is my question, is it possible to generete SQL script which will create exact table as i want? I mean on MySQL GUI tool there is option like this, reverse engineering which generate SQL script which will create exact database as I used function on, is it possible in PostgreSQL in shell level?
pg_dump --schema-only db1 > db-schema.sql
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I am working on a PostgreSQL database and I need to take a backup of specific data from a table and restore it into the same or a different database. I am looking for a way to accomplish this task using command-line tools or scripts.
I have tried using the pg_dump and pg_restore command-line utilities, but they seem to only allow for backing up and restoring an entire database or table, rather than specific data within a table.
Is there a way to take a backup of specific data from a table in PostgreSQL and restore it into a database? If so, could you provide an example of the command or script that would accomplish this task?
Thanks in advance for your help!
We have a series of modifications to a Postgres database, which can generally be written all in SQL. So it seems Flyway would be a great fit to automate these.
However, they also include imports from files to tables, such as
COPY mytable FROM '${PWD}/mydata.sql';
And secondarily, we'd like not to rely on Postgres' use of file paths like this, which apparently must reside on the server. It should be possible to run any migration from a remote client -- as in Amazon's RDS documentation (last section).
Are there good approaches to handling this kind of scenario already in Flyway? Or alternate approaches to avoid this issue altogether?
Currently, it looks like it'd work to implement the whole migration in Java and use the Postgres driver's CopyManager to import the data. However, that means most of our migrations have to be done in Java, which seems much clumsier. (As far as I can tell, hybrid Java+SQL migrations are not expected?)
Am new to looking at Flyway so thought I'd ask what other alternatives might exist with Flyway, since I'd expect it's pretty common to import a table during a migration.
Starting with Flyway 3.1, you can use COPY FROM STDIN statements within your migration files to accomplish this. The SQL execution engine will automatically use PostgreSQL's CopyManager to transfer the data.
Any idea how to go about doing that through a tool(preferred). Any alternate ways to do that.
You can check out the migration studio from EnterpriseDB here, although I have no experience with it.
There is no comparison to doing it yourself though - if you're not familiar with Postgres then this will get you familiar, and if you are, then aside from the data entry aspect, this should be old hat.
Use maxdb tools to generate a SQL text export of the database. Then import this file in PostgreSQL, luckily you won't need prior processing of the data dump.
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 :(
Similar to SQL script to create insert script, I need to generate a list of INSERT from a table to load onto another database (sqlite), like the dump command. I do this for sync purposes.
I have limitations because this will run on a cloud server without acces to the filesystem, so I need to do this in the DB (I can do this in the app server, I'm asking if is possible to do this in the DB directly).
In the app server, I load a datatable, walk his fieldnames and datatypes and build a insert... I wonder if exist a way to do the same in the DB...
I am not entirely sure whether that helps, but you can use simple ETL tool like 'Pentaho Kettle'. I used it once for a similar function and it did not take me more than 10 min. You can also schedule the jobs. I am not sure whether it is supported in database level.
Thanks,
Shankar