Question

Equality, non-equality, and self-joins are all categorized as which type of joins?

1) Inner joins
2) Outer joins
3) Cross joins
4) Natural joins

Answer 1

Equality, non-equality, and self-joins are all categorized as 1) Inner joins.

Step-by-step explanation:

Inner joins, the correct answer, encompass equality, non-equality, and self-joins. They bring together matching records from two tables based on a specified condition using comparison operators like "=", "<>", etc. Equality joins, the most common, retrieve records where values in the specified columns are equal. Non-equality joins use operators like "<", ">", or "<>" to find records that don’t have matching values. Self-joins occur when a table is joined with itself, often comparing values in different rows within the same table.

These joins aid in combining data across tables based on various relationships, playing a crucial role in SQL queries for fetching specific data. Inner joins, unlike outer joins which retain unmatched records, only return matching records from both tables involved. They are fundamental for data retrieval, allowing for the extraction of precisely linked information from multiple sources.

Correct answer: 1) Inner joins