SQL Aliases

Syntax

For column alias

In the above syntax, we can see that we have given an alias for the column name.

For table alias

In the above syntax, we can see that we have given an alias in sql for the table name.

Demo Database

Consider the following table named "India_Offices".

Now we will understand the alias clause by using queries on the above table.

Alias for Columns

Using an alias in sql for columns significantly improves the readability of your query results, especially when the original column names are lengthy or not particularly descriptive. Aliases allow you to assign more understandable or concise names to columns in the output of your queries.

Example:

Consider the "India_Offices" table, which contains columns such as Office_id_India, Location, Target_Area, Employees, and Global_Rank. The column names like Office_id_India and Global_Rank might not be immediately clear or too lengthy for some report outputs. We can use aliases to simplify these names.

Query:

This query assigns more readable aliases to the columns, such as "Office ID" for Office_id_India and "Employee Count" for Employees, making the output more accessible.

Output:

Using Aliases with a Space Character

When incorporating spaces into column names in SQL query results, aliases are essential. These should be enclosed in double quotes (" ") or square brackets ([ ]), depending on your SQL database's syntax requirements. This approach enhances the readability of your query outputs, fitting specific formatting standards or making the data more user-friendly.

Example:

Considering the "India_Offices" table, let's modify the Office_id_India column name to Office ID India for greater clarity in our query results.

Query:

Query for a SQL Database that Supports Double Quotes:

Query for SQL Server (using Square Brackets):

Output:

This query will adapt the Office_id_India column name to Office ID India, including a space in the alias for improved legibility.

Concatenate Columns

To concatenate columns in the "India_Offices" table in SQL, you can use the || operator in standard SQL or + operator in SQL Server. Here's how you can concatenate the "Location" and "Target_Area" columns into a single column named "Office_Location":

Example:

Let's combine Location and Target_Area columns into a single column named Office_Location for a more comprehensive display.

Query:

Output:

The query will produce a single column Office_Location that combines the Location and Target_Area of each record, separated by a space.

Alias for Tables

Utilizing sql alias for tables within SQL queries can significantly enhance the readability and manageability of your queries, especially when dealing with multiple tables or complex joins.

Example

Let's say we have a table named India_Offices, and we want to display the location and target area of each office. To simplify the query, we can use aliases for this table.

Query

Output

The query above would produce an output similar to the following, where io is the alias for the India_Offices table: