How the LIKE Operator Works in SQLite

In SQLite, you can use the LIKE operator in your queries to do a pattern matching comparison.

For example, you can add it to your WHERE clause in order to return only rows that match a given pattern.

However, adding it to the WHERE clause isn’t the only way you can use the LIKE operator. You can also use it to return a boolean value.

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3 Ways to Detect if a String Matches a Regular Expression in MySQL

MySQL has a number of functions and operators that allow us to perform operations using regular expressions (regex). This article presents two operators and one function that enable us to find out if a string matches a regular expression specified by a given pattern.

These regex functions and operators are:

These are all basically equivalent, as the operators (the second two) are both synonyms of the function (the first one). In any case, you can see examples of all three in action below.

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How the MATCH() Function Works in MySQL

In MySQL, the MATCH() function performs a full-text search. It accepts a comma separated list of table columns to be searched.

The table/s must have a FULLTEXT index before you can do a full-text search against them (although boolean queries against a MyISAM search index can work — albeit slowly — even without a FULLTEXT index).

You can create a FULLTEXT index when creating the table (using the CREATE TABLE statement), or you can use the ALTER TABLE statement or the CREATE INDEX statement if the table already exists.

By default, the search is case-insensitive. To perform a case-sensitive search, use a case-sensitive or binary collation for the indexed columns.

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How NOT LIKE Works in MySQL

In MySQL, you can use NOT LIKE to perform a negation of the LIKE operator. In other words, NOT LIKE returns the opposite result to LIKE.

If the string matches the pattern provided, the result is 0, otherwise it’s 1.

The pattern doesn’t necessarily need to be a literal string. This function can be used with string expressions and table columns.

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