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SQL text searches

Text searches are essential functionality in SQL and MySQL, allowing users to find specific information within a database.

These searches can be simple or advanced, depending on the user’s needs.

In this article, we’ll focus on the three most common types of text searches: exact search, partial text search, and full text search.

Also we will compare the search methods to help users choose the most suitable for their needs.

Content

  • Types of searches in SQL and MySQL
    • exact search
    • Partial text search
    • Full text search
    • Search by regular expressions
  • Comparison of SQL search methods

Types of searches in SQL and MySQL

exact search

Exact search is the simplest and most direct method of searching for information in a database.

This search returns accurate results that exactly match the search terms. In SQL and MySQL, exact searching is done using the equals (=) operator.

Example of exact search query in MySQL:

SELECT * FROM productos WHERE nombre = 'Smartphone Samsung Galaxy';

Partial text search

Partial text search is a more flexible method that allows you to search for information based on a part of the text.

This is useful when users don’t remember the full name of the product or don’t know how to spell it exactly.

In SQL and MySQL, partial-text searching is done using wildcards, such as the % sign, and with the LIKE SQL operator.

Example partial text search query in MySQL:

SELECT * FROM productos WHERE nombre LIKE '%Samsung%';

Full text search

Full text search is the most advanced method, allowing users to search for information based on meaning and context.

This type of search is useful when you need to find relevant information in large databases. In SQL and MySQL, full-text searching is done using the MATCH AGAINST command.

Example full-text search query in MySQL:

SELECT * FROM productos WHERE MATCH(nombre, descripcion) AGAINST('Samsung Galaxy S21' IN NATURAL LANGUAGE MODE);

Search by regular expressions

Regular expression search is used to find matches of a text string that meet certain rules defined by the user. To search for regular expressions, the “REGEXP” or “RLIKE” operator is used.

Example:

SELECT * FROM tabla WHERE columna REGEXP 'patrón';

And a more concrete example would be to search for the planets that end in “us”:

SELECT name 
FROM planets
WHERE name LIKE "%us";

Comparison of SQL search methods

Now that we understand the different types of text searches available in SQL and MySQL, it’s important to compare them to understand when to use each.

  • LIKE: This method is useful when you don’t know exactly the keyword you’re looking for, but you have a general idea of ​​it. It is useful for simple searches, but not very efficient for more complex searches or large data sets.

  • MATCH AGAINST: This method is useful for more complex searches that involve multiple keywords and need to find precise and relevant results. It is efficient for large data sets and allows more control over the results, but it requires the creation of a full-text index and only works in MySQL.

  • REGEXP: This method is useful for more complex searches involving specific patterns of characters. It is efficient for large data sets and allows more flexibility in searching, but it requires a deeper understanding of regular expressions and can be slower than other methods in some cases.

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