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How to Retrieve Records that Matches a Pattern: SQL Programming

When retrieving data in sql programming, you can view selected rows that match a specific pattern. For example, to create a report that displays all the product names of Adventure Works beginning with the letter P. This task can be done through the LIKE keyword.

The LIKE keyword is used to search a string by using wildcards. Wildcards are special characters, such as * and %. These characters are used to match patterns and some of them are described with example, mostly used by sql server:

  • %    Represents any string of zero or more character(s)
  • _    Represents a single character
  • []    Represents any single character within the special range
  • [^]    Represents any single character not within the specified range

The LIKE keyword matches the given character string with the specified pattern. The pattern can include combination of wildcard characters and regular characters. While performing a pattern match, regular characters must match the characters specified in the character string. However, wildcard characters are matched with fragments of the character string.

The following SQL query retrieves records from the Department table where the values of Name column begin with ‘Pro’. You need to use the ‘%’ wildcard character for this query.

SELECT * FROM HumanResources.Department WHERE Name LIKE 'Pro%'

Output: Shows all the records satisfy the given condition i.e. starting with Pro

How to Retrieve Records that Matches a Pattern: SQL Programming

The following SQL query retrieves the rows from the Department table in which the department name is five characters long and begins with ‘Sale’, whereas the fifth character can be anything. For this, you need to use the '_wildcard character.

SELECT * FROM HumanResources.Department WHERE Name LIKE 'Sale_'

Output: Shows all the records satisfy the given condition i.e. starting with having sale with single character.

How to Retrieve Records that Matches a Pattern: SQL Programming

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