What does like mean in sql

SQL LIKE operator is used for pattern matching. The syntax is SELECT * FROM table_name WHERE column_name LIKE pattern; The pattern can use wildcard characters % (any character) and _ (single character), and supports escape characters and character ranges. Negative match with NOT LIKE. But be aware that the LIKE operator is case-sensitive and may be slower for large data tables.

LIKE Operator in SQL

The LIKE operator is used for pattern matching in SQL queries. It checks whether a string matches a given pattern.

Syntax:

<code class="sql">SELECT * FROM table_name WHERE column_name LIKE pattern;</code>

Pattern:

The pattern can contain the following wildcard characters:

• %: Matches any number of characters (including 0 characters).
• _: Matches a single character.

Example:

• LIKE 'dog%': Matches any string starting with "dog".
• LIKE '%dog': Matches any string ending with "dog".
• LIKE '%dog%': Matches any string containing "dog".
• LIKE 'd_g': Matches any string containing "d" and "g" with an arbitrary character in between.

Advanced usage:

In addition to wildcards, the LIKE operator also supports other advanced usage:

• Escape characters: Use backslash() in the pattern to escape special characters (such as % and _).
• Character range: Use square brackets ([ ]) to define character ranges. For example, [a-z] matches any lowercase letter.
• Negation: Use the NOT LIKE operator to find strings that do not match a given pattern.

Note:

• The LIKE operator is case-sensitive.
• The LIKE operator can be slow for tables containing large amounts of data.
• In some cases, using the REGEXP operator may be more efficient than the LIKE operator.

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