We will use the Customers table to illustrate the SQL LIKE clause usage:
FirstName LastName Email DOB Phone
John Smith John.Smith@yahoo.com 2/4/1968 626 222-2222
Steven Goldfish goldfish@fishhere.net 4/4/1974 323 455-4545
Paula Brown pb@herowndomain.org 5/24/1978 416 323-3232
James Smith jim@supergig.co.uk 20/10/1980 416 323-8888
The SQL LIKE clause is very useful when you want to specify a search condition within your SQL WHERE clause, based on a part of a column contents. For example if you want to select all customers having FirstName starting with 'J' you need to use the following SQL statement:
SELECT *
FROM Customers
WHERE FirstName LIKE 'J%'
Here is the result of the SQL statement above:
FirstName LastName Email DOB Phone
John Smith John.Smith@yahoo.com 2/4/1968 626 222-2222
James Smith jim@supergig.co.uk 20/10/1980 416 323-8888
If you want to select all Customers with phone numbers starting with '416' you will use this SQL expression:
SELECT *
FROM Customers
WHERE Phone LIKE '416%'
The '%' is a so called wildcard character and represents any string in our pattern.
You can put the wildcard anywhere in the string following the SQL LIKE clause and you can put as many wildcards as you like too.
Note that different databases use different characters as wildcard characters, for example '%' is a wildcard character for MS SQL Server representing any string, and '*' is the corresponding wildcard character used in MS Access.
Another wildcard character is '_' representing any single character.
The '[]' specifies a range of characters. Have a look at the following SQL statement:
SELECT *
FROM Customers
WHERE Phone LIKE '[4-6]_6%'
This SQL expression will return all customers satisfying the following conditions:
* The Phone column starts with a digit between 4 and 6 ([4-6])
* Second character in the Phone column can be anything (_)
* The third character in the Phone column is 6 (6)
* The remainder of the Phone column can be any character string (%)
Here is the result of this SQL expression:
FirstName LastName Email DOB Phone
John Smith John.Smith@yahoo.com 2/4/1968 626 222-2222
Paula Brown pb@herowndomain.org 5/24/1978 416 323-3232
James Smith jim@supergig.co.uk 20/10/1980 416 323-8888
Popular Posts
-
The SQL ORDER BY clause comes in handy when you want to sort your SQL result sets by some column(s). For example if you want to select all t...
-
STRINGS: The way a group of integers can be stored in an integer array, similarly a group of characters can be stored in a character array. ...
-
Declaration of variables In order to use a variable in C++, we must first declare it specifying which data type we want it to be. The syntax...
-
SQL aliases can be used with database tables and with database table columns, depending on task you are performing. SQL column aliases are u...
-
Java Server Pages JavaServer Pages (JSP) technology is the Java platform technology for delivering dynamic content to web clients in a por...
-
A JSP expression is used to insert Java values directly into the output. It has the following form: The Java expression is evaluated, conver...
-
To whom is this tutorial directed? This tutorial is for those people who want to learn programming in C++ and do not necessarily have any pr...
-
Introduction: In this exercise, you are going to build and run a sample Java program called Homework using NetBeans. The sample program can...
-
1 Introducing the .NET Framework with C# The .NET Framework is such a comprehensive platform that it can be a little difficult to descr...
-
Inheritance A key feature of OOP is reusability. It's always time saving and useful if we can reuse something that already exists rather...
No comments:
Post a Comment