acrocord 2023.3.4

Python API for PostreSQL database

A python API for managing postgresql database

Install and setup

Install third party packages:

sudo apt install python3-dev libpq-dev unixodbc-dev

To install the package

python3 -m pip install acrocord

use python in the proper environment e.g. in conda powershell

Setup database configuration and connection

SSL connection: if SSL connection is required, put the certificates given by administrator in /home/$USER/.postgresql create the folder if it does not already exist

Default connection configuration can be saved in connections.cfg in the folder /home/$USER/.postgresql/ for linux user or typically C:\Users\$USER\.postgresql for windows user.

Example of connections.cfg:

[connection-name]
user=USERNAME
dbname=DATABASENAME
port=PORT 
host=HOST
ssh=False
password=PASSWORD

[!TIP]

• the host field does not recognize ssh alias, use ip address
• the port field is typically 5432 or 5433
• the name of the database is dbname

Then in python the connection can directly be instantiate using the keyword connection-name

from acrocord import ConnectDatabase

db = ConnectDatabase()
db.connect(connection="connection-name")

Alternatively, you can use the following syntax

from acrocord import ConnectDatabase

db = ConnectDatabase()
connection = dict(
    user="USERNAME",
    print_sql_cmd=True,
    dbname="DATABASENAME",
    port="PORT",
    host="HOST",
    ssh=False
)
db.connect(print_sql_cmd=True, connection=connection)

Simple usage

import pandas as pd
# create schema (i.e. an independent database: requires privileges)
# write table in schema
# read table as pandas dataframe
db.create_schema("SCHEMA")
db.write_table(pd.DataFrame(1, index=[1, 2, 3], columns=[1, 2, 3]), "SCHEMA.NAME")
db.read_table("SCHEMA.NAME")

[!CAUTION]

• If the password is trivial (for local connection), add password field to the dictionary connection
• Password field can be added in connections.cfg file
• If no password is provided python will open an log in window
• No password is needed with ssl connection

Other topics

• Deploy database: install postresgql server and create database on premise
• Manage spatial data using postgis: how to install postgis and manipulate spatial data

Author

• Eurobios Mews labs