Problem Often when dealing with database records, you might encounter a situation where you want to group records based on a specific column but rather than aggregating the other columns using functions like SUM() or AVG(), you want to concatenate their strings. MySQL has the GROUP_CONCAT() function for this purpose. Input ID Class Name 1 …
How to use GROUP BY to concatenate strings in MySQL and SQL Server? Read More »
Problem Let’s understand the difference between UNION and UNION ALL in SQL with an example. Input Let’s create a table named fruits with columns id, name, and type. We will insert some rows into this table: id name type 1 Apple Fresh 2 Banana Fresh 3 Apple Dried 4 Banana Dried 5 Cherry Fresh Try …
What is the difference between UNION and UNION ALL in SQL? Read More »
Problem Let’s see how to find duplicate values in an SQL table. Input id name enrollment_number 1 Alice ENR123 2 Bob ENR124 3 Charlie ENR125 4 David ENR123 5 Edward ENR126 6 Frank ENR124 Try Hands-On: Fiddle Create Source tables: Code Gist Desired Output enrollment_number count ENR123 2 ENR124 2 Solution 1: Using GROUP BY …
