SQL Wildcards: A Guide to Pattern Matching in Queries

Wildcards are the placeholders that make pattern matching possible. Paired with the LIKE operator, they let you search for text by shape instead of exact value — names starting with a letter, codes ending in a suffix, anything containing a word. SQL has two you’ll use constantly, % and _, plus a bracket form in some databases.

Run the examples live below — a real SQL engine in your browser — and watch each wildcard change what matches.

The two wildcards you’ll use everywhere

Where you place them defines the pattern:

• 'W%' — starts with W (W then anything).
• '%e' — ends with e (anything then e).
• '%o%' — contains an o (anything, o, anything).
• 'W%e' — starts with W and ends with e.

% — any run of characters

The percent sign is the workhorse. It matches zero, one, or many characters, so it’s how you say “starts with,” “ends with,” or “contains”:

SELECT name
FROM products
WHERE name LIKE '%Scarf%';

Because % also matches nothing, 'Scarf%' matches both “Scarf” and “Scarf Wool” — the trailing % is happy to match an empty string.

_ — exactly one character

The underscore matches a single character — no more, no less. Use it when position matters:

SELECT name
FROM customers
WHERE name LIKE '_i%';

That pattern means: any first character, then i, then anything — i.e. names whose second letter is i. Swap in more underscores to pin down more positions: '____' matches any exactly-four-character value.

Combining wildcards

Mix % and _ and add literal characters to describe precise shapes:

SELECT name
FROM products
WHERE name LIKE 'W%e';

Start with W, allow anything in the middle, end with e. You can stack them — '_a%t' means “second letter a, ending in t” — as specific as you need.

The bracket wildcard [ ] (SQL Server)

SQL Server (and MS Access) add a third form: square brackets match any one character from a set or range.

-- SQL Server only
WHERE name LIKE '[ACW]%'   -- starts with A, C, or W
WHERE code LIKE '[0-9]%'   -- starts with a digit
WHERE name LIKE '[^A]%'    -- does NOT start with A

This is not standard SQL — PostgreSQL, MySQL, and SQLite don’t support [ ] in LIKE (you’d use a regular expression like ~ or REGEXP instead). This playground follows the portable % / _ behavior, so the bracket form is shown here for reference only.

Escaping a literal % or _

To search for an actual percent sign or underscore, escape it with your database’s ESCAPE clause so it’s treated as a literal:

WHERE discount_code LIKE '50\% off' ESCAPE '\'

Practice

Frequently asked questions

What are the wildcards in SQL? % matches any run of characters (including none), and _ matches exactly one character. SQL Server also supports [ ] for a character set or range. They’re used with LIKE.

What’s the difference between % and _? % matches any number of characters; _ matches exactly one. 'A_' matches a two-character value starting with A; 'A%' matches any value starting with A.

Do wildcards work in MySQL and PostgreSQL? % and _ work everywhere. The bracket form [ ] is SQL Server / Access only; elsewhere use a regular expression (REGEXP in MySQL, ~ in PostgreSQL).

How do I match a literal % sign? Escape it with the ESCAPE clause: LIKE '50\% off' ESCAPE '\'.

From patterns to pipelines

Wildcard matching is one way to filter text. When that filtering runs continuously across data sources, ET1 makes it a visual Filter node with a live preview of matching rows.

Keep going: see the LIKE operator that wildcards plug into, match a list of exact values with IN, or combine conditions with AND, OR, and NOT.