Category Archive : MySQL

A sub-query is a SQL query that is used inside another query.

There is no specific pattern for sub-query. Sub-query is used when need to query from another or multiple tables and show data.

Suppose, you have to query with … Read more

The GROUP BY statement is used with aggregate functions (COUNT, MAX, MIN, SUM, AVG) to group the result set by one or more columns.


SELECT column_name FROM table_name GROUP BY column_name;
SELECT column_name1,column_name2 FROM table_name GROUP BY column_name1,column_name2;
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If you want to sort data, then you have to use order by clause. If you want to sort data in ascending order, then you have to use the following query:


select * from table_name order by column_name ASC;
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Insert Data

Now we will add some data using the SQL insert query

Insert query pattern:

insert into table_name (column1,column2,column3,……..columnN) values (‘value1′,’value2′,’value3′,……….,’valueN’);

Now insert some data into our newly created table using this query:

INSERT INTO employees (Emp_id,FirstName,LastName,Department,Designation,Salary) VALUES ('1001','Abdur', 
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SQL commands are 4 types. DDL, DML, DCL and TCL

Here I am describing about the SQL Commands.


DDL is the short name of Data Definition Language. It used to create, update, and delete database schemas and their … Read more