![]() ![]() ![]() What is pgAdmin? It is a graphical PostgreSQL database management program. It's a great tool that has never let me down. I got used to pgAdmin and honestly I don't see any point in changing to anything else. There are tons of different SQL editors on the market that support PostgreSQL. If you’ve read that article, you know that Postgres is easy to set up and one of the most popular DBMSs in the world. Some time ago, my friend Ignacio showed you how to install and set up PostgreSQL on Windows 10. I think you understand the uses and advantages of CSVs, so let’s move on to the tool we’ll use to import them: pgAdmin. This is a very tiny data set, but you can imagine what it would be like with many columns and thousands of rows. Here’s the same information in CSV format: I wonder if you recognize the data I put there. Have a look at the differences between storing data in a table and storing it in a CSV. In addition, CSVs are text files and thus are quite small transferring even large data sets is not a problem. CSVs are the surest way to save your data they are read by almost all office suites and database management systems (DBMSs). Imagine that you need to export data from a database to a spreadsheet or vice versa. When are CSV files used? Transferring data from one program or platform to another is a main use. This standard is supported by many applications and programs, including Microsoft Office, LibreOffice, and Google Sheets. It is a format for storing data in text files. Don’t worry – it’s easy! What Is a CSV file?ĬSV is short for comma-separated values. We’ll start by explaining what a CSV file is, then we’ll introduce you to pgAdmin and show you how to do the import process. Let's get right into importing CSVs into a Postgres database. Please note that if you are running PostgreSQL on a Windows server, file paths will need to utilise a double-backslash.Do you work with data and use CSV files? Here is a practical guide on how to import such files into a PostgreSQL database using pgAdmin, one of the best PostgreSQL editors on the market. The file can then be accessed and downloaded via WinSCP or another FTP programme. This is the location where the CSV file will be found (or the /csv-output/ subdirectory in our case). To determine the current working directory in psql, enter the following command: \! pwd To answer that question, we need to see where STDCOPY is placing it, which is the current working directory. The question then arises where specifically is the CSV file? (psql actually initiates the STDCOPY function when using COPY). This means that file accessibility and privileges are those of the local user, not the server and no SQL superuser privileges are required. This is an operation that runs an SQL COPY command, but instead of the server reading or writing the specified file, psql reads or writes the file and routes the data between the server and the local file system. The \COPY command (as opposed to COPY) performs a frontend (client) copy operaton. You will notice that we need to exclude the trailing semicolon in our database query for this command. We have specified a comma as the delimiter and want the table headers included. What this says is that we want to copy the output from our query to a CSV file called “csv_file.csv” on our server in a folder called “csv-output”. If we wanted to send all of the results from our database query to a CSV file, we can do this via the \COPY command: \COPY (SELECT * From Table_Name WHERE Column_Name LIKE 'Foo%') TO 'csv-output/csv_file.csv' WITH CSV DELIMITER ',' HEADER This is beyond the scope of this article. There are many variations of this SELECT function. In this example, we want to look into a Table called “Table_Name” and search everything (*) in the column “Column_Name” for entries that contain “Foo” at the start (hence the % wildcard). Then enter a command in the following format: SELECT * From Table_Name WHERE Column_Name LIKE 'Foo%' When using psql, the general method for querying data is to log into a database in PuTTY: psql Database_Name Username If you need to export data from a PostgreSQL database in psql, there is a fairly easy way to do this wouthout requiring superuser privelleges. Export the contents of a database table to a CSV file using the psql PostgreSQL utility in PuTTY. ![]()
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