How to find odd/even rows in sql, duplicate rows, how to delete duplicate rows, constraints, Joins, Ddl dml, diff truncate/delete

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SQL queries for finding odd/even rows, duplicates, and deleting duplicates. Also covers constraints, joins, and DDL/DML differences.

To find odd/even rows, use the MOD function with a value of 2
To find duplicate rows, use the GROUP BY clause with the HAVING clause
To delete duplicate rows, use the DELETE statement with a subquery
Constraints ensure data integrity by enforcing rules on columns or tables
Joins combine data from multiple tables based on a common column
DDL (Data Definition Language) is used to create or modify database objects
DML (Data Manipulation Language) is used to insert, update, or delete data
TRUNCATE is a DDL command that removes all data from a table, while DELETE is a DML command that removes specific rows

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