SQL MID() function

The MID() function is used to extract characters from text fields.

SQL MID() syntax 

SELECT MID(column_name,start[,length]) FROM table_name;

parameter describe
column_name Required.To extract the fields of characters.
start Required.The start position (the start value is 1).
length Optional.The number of characters to return.If omitted, the MID () function returns the remaining text.

Demonstrate the database

In this tutorial, we'll use the well-known Northwind sample database.

Here's the data from the "Customers" table:

CustomerID CustomerName ContactName Address City PostalCode Country
1

Alfreds Futterkiste Maria Anders Obere Str. 57 Berlin 12209 Germany
2 Ana Trujillo Emparedados y helados Ana Trujillo Avda. de la Constitución 2222 México D.F. 05021 Mexico
3 Antonio Moreno Taquería Antonio Moreno Mataderos 2312 México D.F. 05023 Mexico
4

Around the Horn Thomas Hardy 120 Hanover Sq. London WA1 1DP UK
5 Berglunds snabbköp Christina Berglund Berguvsvägen 8 Luleå S-958 22 Sweden

SQL MID() instance

The following SQL statement extracts the first 4 characters from the "City" column of the "Customers" table:

SELECT MID(City,1,4) AS ShortCity
FROM Customers;