What Are the 5 Basic SQL Queries?

 



In SQL query interview questions, the focus often revolves around popular SQL queries that frequently arise. Among these queries are five commonly asked: SELECT, INSERT, UPDATE, DELETE, and JOIN. 

You will find the introduction to these five queries and their syntax in today's blog. Moreover, you will also learn about the applications of these queries. 


  • SELECT Query

The SELECT query is a crucial query to cover for SQL query interview questions. The SELECT query helps the user to extract information from the databases. It makes it really easy to retrieve data and information from extensive databases. 

It is important to be familiar with five main components in the SELECT query when preparing for SQL query interview questions.


Applications of SELECT Query


  • Filtering Data with WHERE Clause

The WHERE clause allows you to specify logical operators such as equality, comparison, and logical conditions to narrow down the data retrieved. The logical operators used in WHERE clauses are AND and  OR.


  • Sorting Results with ORDER BY Clause

The ORDER BY clause is essential for presenting the retrieved data in a meaningful order. It sorts the data based on one or more columns in ascending or descending order. 


  • Limiting Results with LIMIT Clause

The LIMIT clause comes to the rescue when you only need a specific number of rows from the query results. You can efficiently control the output and avoid unnecessary data retrieval by specifying the desired number of rows.


  • INSERT Query

The second important query for your SQL query interview questions is the INSERT query. This query allows you to add new data to your database tables. The INSERT query is crucial in populating your database with valuable information, whether creating a new record or inserting multiple rows simultaneously. 


Syntax and Structure of the INSERT Query

Here, `table_name` represents the table's name where you want to insert data. The columns you want to populate are specified within parentheses, separated by commas. The corresponding values for these columns are provided in the VALUES clause, also separated by commas.


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