DbSchema Database Designer

DbSchema | How to Generate Random Data in PostgreSQL

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When developing an application, if you want to test it right an empty database is not very useful. To make sure that everything is working
you have to generate tests that are very close to real life situations. That means populating the database with meaningful and
statistically correct data.

Writing complex data generators is time consuming. That’s why DbSchema integrates a smart Data Generator that can be easily used to
populate PostgreSQL databases with random data.

The Data Generator can generate dedicated patterns for numbers, date, booleans etc. that start with a keyword like int, short, sequence
etc. Any other pattern that doesn’t start with one of those keywords will be interpreted as Reverse Regular Expression.

Let’s see how easy it is to generate random data in PostgreSQL databases.

To open the data generator, just right click on the table and choose Data Generator from the menu. If you want to generate data in
more than one table, drag the tables in a new layout and right click on an empty space.

open data generator

When the data generator dialog opens, DbSchema automatically attributes some data patterns based on the columns’ name and data type. From here
you can edit the columns that have a pen icon near the name (Generator, Nulls, Seed).

data generator dialog

  • Nulls represent the percentage of null cells you want to apply to the table;
  • Seed two columns with the same positive seed will generate the same sequence of values;
  • Generator is the data patterns. To edit, double-click on the pattern. This will open a new pattern editor:

pattern editor

From here you can write your own pattern or choose from the repository.

pattern repository

After everything is set, click on the To Generator button and you’re almost done.

data generator

f you have more than one table in the generator, from here you can exclude some of them or add more. Also, you can preview how the data will
look in the table by pressing the Sample Data button.

After you click on Generate, the message All Done will show in the Message column. If there are any errors, they will also appear
in that column.

To verify the data, exit the generator and click on the tables’ header while pressing SHIFT + CTRL. This will open a quick-view.

quick view

This is how you can generate meaningful data in your PostgreSQL database in less than 5 minutes.

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Visually Manage Databases using DbSchema

DbSchema is a databases client and visual designer. DbSchema has a free Community Edition, which can be downloaded here.
DbSchema main features include:

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Interactive Diagrams

Design tables, column and foreign keys directly in diagrams, by double-clicking them. Changes will be saved to the design model and, if DbSchema is connected to the database also into the database. More.


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Simple Connection Dialog

Choose the database location, the user and password, and simply get connected. Choose 'Edit Manually' into the JDBC URL combo to enter a custom URL. More.


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Relational Data Explorer

Explore data from multiple tables simultaneously, using foreign keys or virtual foreign keys. Double-click cells to edit the data. More.


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Query Builder

Create SQL Queries featuring JOINS, GROUP BY, ORDER BY just using the mouse. More.


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SQL Query Editor

Edit and execute SQL Queries. The editor is autocompletion-enabled. More.


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Design Schema in Team & Schema Deployment

DbSchema is using the design model, a copy of the schema structure, independent of the database.
The design model can be saved to file and shared in a team.
Connecting to another database you may compare the design model with the database, commit the differences or merge them in the design model. More.


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Dark Theme

Configurable styles & dark theme. More.


Many features are available in the free Community edition.
The Pro edition adds capabilities to save the design to the model file, design schema in team and deploy the schema on multiple databases.


DbSchema can be downloaded for free. No registration is required.