intro
This blog post will inform readers about the several data types in Postgres, which are the different types of data that can be stored in a Postgres database while using a tool like DbVisualizer to manage these data types.
This blog post will inform readers about the several data types in Postgres, which are the different types of data that can be stored in a Postgres database while using a tool like DbVisualizer to manage these data types.
Preface
Data types in PostgreSQL define the type of data that can be stored in a table column and help ensure the accuracy and efficiency of data storage and retrieval. Postgres offers a wide range of data types, each coming with its specific characteristics.
PostgreSQL is also unique in that it has 43 data types, more than any other database management system available on the market - with each of these data types serving a unique purpose, storing data doesn’t get much fancier than that.
This article will demonstrate the process of connecting to a Postgres database using DbVisualizer, creating tables, and inserting data with its appropriate data type into the tables. This will give readers an edge in comprehending data types in a Postgres database and how to manage them efficiently using DbVisualizer.
Understanding PostgreSQL data types
In computing, data types are categories that specify the kind of data that a variable or an expression can hold. Data types define the format, range, and operations that can be performed on data. They tell the type of data that can be stored in the column of a table and determine the correct interpretation and manipulation of the data. As already mentioned above, Postgres offers a wide range of data types. Let us look at some of the data types in Postgres:
Character data types in PostgreSQL
Character data types are used to store text data. Postgres offers three different character data types: character varying (varchar), text, and character.
Numeric data types in PostgreSQL
Numeric data types are used to store numerical data. Postgres offers four different numeric data types: integers, floating-point numbers, fixed-point numbers, and booleans.
Date and time data types in PostgreSQL
Date and time data types are used to store date and time values. Postgres offers four different date and time data types: date, time, timestamp, and time with time zone (timestamptz).
Other data types in PostgreSQL
Postgres also offers some other data types, including arrays, geometric data types, JSON and JSONB data types, range types, and network address data types.
The Significance of PostgreSQL Data Types
PostgreSQL data types are important for several reasons. They ensure that data is stored and subsequently processed successfully. Specifying the type of data that can be stored in a column also helps prevent common programming mistakes, enables efficient memory location by determining the appropriate amount of space required for different types of data, and enhances the readability of code by making it clear what kind of data is being handled and how it should be interpreted.
How to Select the Correct PostgreSQL Data Type
When choosing data types, there are some factors to consider: the data type, the size of the data, the performance requirements, the portability needs, etc.
When taken into careful consideration, these factors help utilize memory space and improve the performance of database applications.
How to use PostgreSQL data types
As a sequel to the factors to consider when selecting a data type, let us also keep these in mind:
PostgreSQL data types in a database client like DbVisualizer
DbVisualizer can help Postgres users manage and query data types by providing information about data types, allowing the conversion of data type and validation, and also, querying data by data type and also providing a user-friendly interface for managing and querying data in the database. To be able to visualize the integration of DbVisualizer with Postgres, we will have to follow a few steps:
Step 1: Connecting To The Database Server
Firstly, we'll need to employ DbVisualizer to establish a connection to our database server. In today’s lesson, we’ll be using the Postgres database server. We can establish a connection to a database server in DbVisualizer by creating a new database connection from the "Create Database Connection" menu, selecting a driver for your database, entering the connection details such as the name, database type, server IP, port, user account, and password and clicking "Connect" to access the database as shown in the image below:

Step 2: Working with Postgres Using DbVisualizer
Now we will create a table with multiple data types, insert data into it, and visualize everything with DbVisualizer.
Creating a Table and Adding Columns
Click on the plus icon to open the SQL commander.

Let us build a SQL query in which a “transactions” table will be created with multiple columns.

1
CREATE TABLE transactions (
2
transactionId INTEGER PRIMARY KEY,
3
item VARCHAR(50) NOT NULL,
4
description VARCHAR(2000) NULL,
5
date DATE NOT NULL,
6
quantity INTEGER NOT NULL
7
);
Now, let us verify that the transactions table has been created by navigating postgres>Schemas>public>Tables and right-clicking to refresh the objects tree as shown below:

We can see that the table has been created successfully.

Inserting Data into Table Columns
Let us execute the following query to insert data into the ‘transactions’ table columns:

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INSERT INTO transactions (transactionId, item, description, date, quantity)
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VALUES (1, 'Rice', 'A bag of rice', '2023-11-09', 10),
3
(2, 'Juice', 'Orange juice', '2023-11-10', 5),
4
(3, 'Beer', 'Scottish Whiskey', '2023-11-11', 18);
Data has been successfully inserted into the “transactions” table.

Conclusion
In conclusion, selecting the appropriate data types for each column is important in database management as it ensures that data is stored and subsequently processed successfully. We also learned that defining the type of data that can be stored in a column enables efficient memory location by determining the appropriate amount of space required for different types of data.
DbVisualizer’s user-friendly interface allows for easy connections to several databases including Postgres databases. It allows the creation of tables with different datatypes within its SQL Commander, insertion and retrieval of data, etc. By utilizing DbVisualizer, DBAs can effectively manage their Postgres databases and can help them ensure the accuracy and efficiency of data storage and retrieval.
To learn more about database management, make sure to keep an eye on our SQL Blog, and until next time.
FAQs
What are the different PostgreSQL data types?
Postgres supports a wide variety of data types, including numeric, character, boolean, date and time, interval, etc.
What are some of the common data type errors in PostgreSQL?
Some of the common data type errors in PostgreSQL include:
How do I convert a column from one data type to another in PostgreSQL?
To convert a column from one data type to another in Postgresql, you can use the ALTER TABLE
statement. For example, to convert the transactionId column from an integer
to a numeric
data type, you would use the following statement:

What are the three types of Character data types in PostgreSQL?
The three types of character data types in PostgreSQL are the character varying (varchar), text, and character.
How do I select the correct PostgreSQL data type?
To select the correct PostgreSQL data type, know the type of data, the size of the data, and the performance requirements of the database application, etc. These factors come together to improve the performance of the database application.