How to Transform SQL Queries to Crosstabs in PostgreSQL

A SELECT SQL query retrieves data from a database in a tabular form. The first row, or header row, has the column names, and all the other rows have the data that was retrieved. In a crosstab, the data is condensed and the names of one or more columns are rotated. You can add row and column totals to a crosstab. For example, a list of salesmen’s monthly sales may include the months into the column headers.

Installing MS SQL Server 2019 on Parrot OS

Introduction Parrot OS is a light Linux distribution based on Debian. Microsoft SQL Server or SQL Server is a relational database management system (RDBMS) developed by Microsoft. Starting with SQL Server 2017, Microsoft added Linux support and thus making any newer versions cross platform. This post steps through the process of SQL Server 2019 Developer edition installation on Parrot OS and contains the following topics: downloading and configuring MS SQL Server 2019 package repository running the SQL Server setup process installation of SQL Server command line tools installation Azure Data Studio running queries in Azure Data Studio The commands used in this post will also work on any Debian based distribution like Ubuntu, MX Linux, Linux Mint, Knoppix among many others.

How to Drop All Tables in PostgreSQL Database

Introduction The DROP TABLE command in PostgreSQL removes a table definition, all data and indexes of a table from a database. DROP TABLE will fail if the table has other objects that depend on it like views and foreign key definitions. The command will also fail and display a table does not exist message if the table being dropped does not exist. PostgreSQL does not have a drop all tables command and you have to define your own way of performing this task.