Often we are given a csv of data, and we would like to now how to copy that data directly to a SQL table. Using the COPY command, we can do that easily. In this article, we will learn how to use the COPY command in PSQL.
The basic syntax of COPY is as follows:
COPY [tablename]([columns]]) FROM 'C:\sampledb\data.csv' DELIMITER ',' CSV HEADER;
We will be using docker in this article, but feel free to install your database locally instead. Once you have docker installed, create a new file called
docker-compose.yml and add the following.
version: '3' services: db: image: 'postgres:latest' ports: - 5432:5432 environment: POSTGRES_USER: username POSTGRES_PASSWORD: password POSTGRES_DB: default_database volumes: - psqldata:/var/lib/postgresql phpmyadmin: image: phpmyadmin/phpmyadmin links: - db environment: PMA_HOST: db PMA_PORT: 3306 PMA_ARBITRARY: 1 restart: always ports: - 8081:80 volumes: psqldata:
Now, navigate to
http://localhost:8081/ to access phpMyAdmin. Then log in with the username
root and pass
Click the SQL tab and you are ready to go.
In this article, we will need some data to work with. If you don't understand these commands, don't worry, we will cover them in later articles.
We will be using the sample db provided here: https://dev.mysql.com/doc/sakila/en/. However, we will only enter what we need rather than import the whole db.
Next, let's create an
employee table. This is a slightly simplified version of the sakila database.
CREATE TABLE employees ( emp_no INT NOT NULL, birth_date DATE NOT NULL, first_name VARCHAR(14) NOT NULL, last_name VARCHAR(16) NOT NULL, gender VARCHAR(1), hire_date DATE NOT NULL, PRIMARY KEY (emp_no) );
Now that we have a table, create a csv file with the following information.
"emp_no","birth_date","first_name","last_name","gender","hire_date" 10001,1953-09-02,Georgi,Facello,M,1986-06-26 10002,1964-06-02,Bezalel,Simmel,F,1985-11-21 10003,1959-12-03,Parto,Bamford,M,1986-08-28 10004,1954-05-01,Chirstian,Koblick,M,1986-12-01 10005,1955-01-21,Kyoichi,Maliniak,M,1989-09-12 10006,1953-04-20,Anneke,Preusig,F,1989-06-02 10007,1957-05-23,Tzvetan,Zielinski,F,1989-02-10 10008,1958-02-19,Saniya,Kalloufi,M,1994-09-15
Now copy the path of your file. Then let's import the data using the following.
COPY employees FROM [filepath] DELIMITER ',' CSV HEADER;
Now, select your data and you should have the following.
SELECT * FROM employees e ;