In this article we will look into the process of inserting data into a PostgreSQL Table using Python. To do so follow the below steps:
- Step 1: Connect to the PostgreSQL database using the connect() method of psycopg2 module.
conn = psycopg2.connect(dsn)
- Step 2: Create a new cursor object by making a call to the cursor() method
cur = conn.cursor()
- Step 3: Now execute the INSERT statement by running the execute() method
cur.execute(sql, (value1,value2))
- Step 4: After inserting the data call the commit() method to make the changes permanent.
conn.commit()
- Step 5: Now terminate the cursor and the connection to the database.
cur.close() conn.close()
Example:
For example we will use the Student table of the school database that we created in the earlier sections of the article series.
Here we will create a insert_student() function to insert student_name row to the student table:
Python3
#!/usr/bin/python import psycopg2 from config import config def insert_student(student_name): """ insert a new vendor into the vendors table """ sql = """INSERT INTO students(student_name) VALUES(%s) RETURNING student_id;""" conn = None student_id = None try: # read database configuration params = config() # connect to the PostgreSQL database conn = psycopg2.connect(**params) # create a new cursor cur = conn.cursor() # execute the INSERT statement cur.execute(sql, (student_name,)) # get the generated id back student_id = cur.fetchone()[0] # commit the changes to the database conn.commit() # close communication with the database cur.close() except (Exception, psycopg2.DatabaseError) as error: print(error) finally: if conn is not None: conn.close() return student_id |
Now to verify the insertion use the following command in the psql shell:
SELECT * FROM student;
Output:
