I have been using postgres to build a large database for my research, and I need to export the database to allow my users to use the database I have developped.
In the past I have been exporting database in .csv file and it was a stable choice, but my users have all sorts of problem when import the .csv file, and settting up the database, and create index.
I am wondering if I can help users to preserve all the necessary information like index and view, in my database export, so users can just import the file and no need to touch the database I prepared for them. I am wondering exporting sql dump will help me do that?
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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!
I'm attempting to mock a database for testing purposes. What I'd like to do is given a connection to an existing Postgres DB, retrieve the schema, limit the data pulled to 1000 rows from each table, and persist both of these components as a file which can later be imported into a local database.
pg_dump doesn't seem to fullfill my requirements as theres no way to tell it to only retrieve a limited amount of rows from tables, its all or nothing.
COPY/\copy commands can help fill this gap, however, it doesn't seem like theres a way to copy data from multiple tables into a single file. I'd rather avoid having to create a single file per table, is there a way to work around this?
I need to link an external dbf table into an existing PostgreSQL database. I managed to import that table into PostgreSQL but that creates a copy and therefor redundant data. The dbf table is the attribute table of a shapefile, but I don’t need the spatial aspect of it.
The exercise is part of a project to move data from an MS Access database to PostgreSQL hoping that the data then become accessible from QGIS. Th dbf table is at the moment linked into the MS Access database and used in queries (views) which I want to re-build in PostgreSQL.
I found lots of posts about importing dbf tables into but nothing which would work about linking a dbf table. The closest I got was the Foreign Data Wrapper, but I didn’t manage to use it for my purpose. I’m using PostgreSQL with pgAdmin 4.24.
Many thanks
The exercise is part of a project to move data from an MS Access database to PostgreSQL hoping that the data then become accessible from QGIS.
If you must use PostgreSQL in order to provide access to your spatial data from QGIS, I see no other option than importing the shapefile into PostgreSQL (PostGIS). If for whatever reason you do not need the geometries, you can drop the geometry column after importing the shapefile into the database:
ALTER TABLE table_name DROP COLUMN column_name;
Alternative scenario:
If we're talking about static shapefiles and you don't really need to use PostgreSQL, you can use GeoServer to publish this shapefile via Web Feature Service (WFS) - it is at least what I do in small projects. The easiest option would be to copy the shapefiles into a so called GeoServer Data Directory and publish them afterwards. After that you'd be able to access the data from QGIS using its WFS Client.
I have a CSV file whose data is to be imported to Postgres database , I did it using import function in pgadmin III but the problem is my CSV file changes frequently so how to import the data overwriting the already existing data in database from CSV file ?
You can save WAL logging through an optimization between TRUNCATE/COPY in the same transaction. The basic idea is to wipe the database table with TRUNCATE and reimport the data with COPY. This doesn't need to be done manually with pgAdmin each time. It can be scripted with something like:
BEGIN;
-- The CSV file is 'mydata.csv' and the table is 'mydata'.
TRUNCATE mydata;
COPY mydata FROM 'mydata.csv' WITH (FORMAT csv);
COMMIT;
Note that it requires superuser access to work. The COPY command also takes various arguments, so you can adjust for different settings for null and headers etc.
Finally it should be noted that you ideally want these both to be in the same transaction. I'm not going to over-complicate this example here though as this level of care isn't needed in many of the real-world sorts of cases where one is copying in a CSV file. If you think your situation needs it, it's not too hard to track down.
I have a table in an MS Access db that I want to export to a PostgreSQL database. Every 2 or so months, I want to move all records from the Access table to a table in Postgres.
Right now, I am using the Export to ODBC option in Access to do this, but every time it exports as an entirely new table in Postgres. Is there a way for me to routinely append the records in the Access table to an existing table in my Postgres database? I have come across the option of a FDW but I am not familiar with how to install/use it.
I am new to using PostgreSQL, and have little to no experience working with databases other than Access, so any input/advice would be greatly appreciated.