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5 Ways to Check if a Table Exists in MySQL

November 15, 2025November 17, 2021 by Ian

Here are five ways to check whether or not a table exists in a MySQL database.

How to Return Query Results as a Comma Separated List in PostgreSQL

November 16, 2021 by Ian

In Postgres, we can use the STRING_AGG() function to transform our query results into a comma separated list.

Instead of each value being output in a separate row (as with any regular query), the values are output to a single row, separated by a comma (or some other delimiter of our choosing).

How to Generate a Random Integer Within a Range in MariaDB

November 15, 2021 by Ian

MariaDB includes a RAND() function that returns a random number. More precisely, it returns a DOUBLE precision floating point value v in the range 0 <= v < 1.0.

This is great, but what if you want to generate an integer within a larger range – and a range that you specify?

Fortunately, there’s an easy technique for doing this.

Fix: “operator does not exist: integer || integer” in PostgreSQL

November 15, 2021 by Ian

If you get the “operator does not exist: integer || integer” error in PostgreSQL, it’s probably because you’re trying to concatenate two numbers.

If you really want to concatenate two numbers, the easiest way to overcome this issue is to cast at least one of them to a string data type first.

Another way to do it is to use the CONCAT() function.

2 Ways to List all Stored Procedures in MySQL

November 14, 2021 by Ian

Below are two options for returning a full list of stored procedures in MySQL.

How to Generate INSERT Statements from a Query when using SQLcl (Oracle)

November 13, 2021 by Ian

When using SQLcl with Oracle Database, you can set SQLFORMAT to insert in order to output the query results as INSERT statements.

Fix: “BACKUP LOG cannot be performed because there is no current database backup.” in SQL Server/SQL Edge

November 13, 2021 by Ian

If you’re trying to back up the transaction logs in a SQL Server or SQL Edge database, but you get an error that states BACKUP LOG cannot be performed because there is no current database backup, you’ll need to perform at least one full backup of the database before you attempt to back up the transaction logs.