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Tag Archives: SQL Tutorial

SQL Group By Clause

Let’s understand the working of SQL Group By Clause. In SQL, Group By clause can be used in a SELECT statement to collect data across multiple records and group the results by one or more columns.   The GROUP BY statement is used in conjunction with the aggregate functions to group the result-set by one or more columns. … Continue reading SQL Group By Clause

UPDATE Statement in SQL

Let’s understand Update Statement in SQL. In SQL,  UPDATE statement is used to update the records or data present in the table. The SQL UPDATE command changes the data which already exists in the table. Usually, it is needed to make a conditional UPDATE in order to specify which row(s) are going to be updated. The WHERE clause is … Continue reading UPDATE Statement in SQL

INSERT in SQL

Let’s understand Insert in SQL. In SQL,  INSERT statement is used to insert the records or data into the table.   The SQL INSERT statement is used to insert a single record or multiple records into a table. If the columns are not specified, it means that values are added for all of the columns … Continue reading INSERT in SQL

Union and UnionAll in SQL

Let’s understand the difference in Union and UnionAll in SQL. SQL supports few Set operations to be performed on table data. Set operators combine the results of two component queries into a single result. Queries containing set operators are called compound queries.   In SQL, We have 4 types Set Operators – UNION – All distinct … Continue reading Union and UnionAll in SQL

Subquery in SQL

Let’s understand the concept of Subquery in SQL. In SQL, Subquery is the query in the query. A subquery is also called nested query or inner query. SQL subquery is usually added in the WHERE Clause of the SQL statement.   A subquery is a query that is nested inside a SELECT, INSERT, UPDATE, or DELETE statement, or inside … Continue reading Subquery in SQL

SQL Outer Join

In SQL, Outer Join keyword returns all rows from both the participating tables which satisfy the join condition along with rows which do not satisfy the join condition. The SQL OUTER JOIN operator (+) is used only on one side of the join condition only.   Outer Join is three types – Left Outer Join Right Outer Join … Continue reading SQL Outer Join

SQL Inner Join

SQL Inner Join keyword selects all rows from both tables as long as there is a match between the columns in both tables.   Inner join returns only those records/rows that match or exists in both the database tables. SQL Syntax : SELECT column1, column2 FROM table1 INNER JOIN table2 ON table1.column=table2.column;   The INNER JOIN in SQL joins two tables according … Continue reading SQL Inner Join