handle large data sizes in PostgreSQL with COPY MANAGER

Copying large volumes of data in and out of a PostgreSQL database efficiently is a common challenge faced by database administrators and developers. In this article, we will explore practical examples of using Copy Manager to handle large data sizes in PostgreSQL effectively.

It is often seen that copy and exporting data using Java code or in Spring boot takes considerable amount of time . As a solution we have copy manager .

What is a Copy Manager In PostgreSQL ?

The Copy Manager, is also known as COPY command . It is really crucial and powerful feature in PostgreSQL for efficiently handling bulk data loading and export . In this in-depth overview, we’ll explore the various utilities of the Copy Manager in PostgreSQL, its use cases, syntax, options, and best practices.

Copy Manager Syntax

The basic syntax for the COPY command in PostgreSQL is as follows:

COPY table_name [ ( column_name [, ...] ) ]
FROM { 'filename' | PROGRAM 'command' | stdin | stdout | pstdin | pstdout }
[ [ WITH ] ( option [, ...] ) ]

Copying Data In (Importing from CSV) with Copy Manager

When you need to import a large dataset into a PostgreSQL table, Copy Manager is the tool of choice for its speed and efficiency. Let’s walk through an example of how to copy data into a PostgreSQL table using the COPY command from a CSV file . Lets take a file name users_data.csv which has users data such as id ,name and age .

Lets create a table to store the csv data .

CREATE TABLE users (
    id SERIAL PRIMARY KEY,
    name VARCHAR(255),
    age INT
);

Now in order to import that data in table called as USERS created above using copy Manager .

COPY USERS(name, age) FROM '/path/to/users_data.csv' CSV HEADER;

In this above example, we create a table called USERS with columns name and age.
We then use the COPY command to import data from a CSV file into this table. Copy Manager handles the data loading efficiently, even for large datasets.
The ‘CSV HEADER‘ option indicates that the first row of the CSV file contains column headers.

Note :- Time Taken for 3Million Records is approx 5 Minutes . Now you understand the power of this utility ?

Copying Data Out (Exporting from Table in CSV ) with Copy Manager

Exporting data from a PostgreSQL table to an external file such as csv is equally simple with Copy Manager.

Let’s look at an example of how to copy data out of a PostgreSQL table and save it to a CSV file.

Lets export using the above example , we want to export data from users table and export to a file named users_exported.csv .

COPY USERS TO '/path/to/users_exported.csv' CSV HEADER;

In this example, we are again using the COPY command , but this time to export data from the USERS table to a CSV file. Copy Manager ensures that the data is efficiently exported, even if the table contains a large amount of information.

Performance Tips

If you are working on large dataset in PostgreSQL , here are some of the performance improvements that you can try .

Divide largee volume of data in several small volumes and try loading , although copy manager will still work but it will be bit slower.
Try disabling indexes and Vaccum while uploading data in postgresql using copymanager . This will speed up data import
Implement proper error handling and logging to address any issues that may arise during data loading.

Conclusion

Copy Manager is a powerful tool for handling large data sizes effectively wheather you are a database admin or a developer . Whether you need to import data from external sources or export data for analysis, Copy Manager is one of the best and reliable solutions in world of PostgreSQL .