SQL Wildcard Characters – Complete Guide with Examples (2026-27)

✅ What are SQL Wildcard Characters?

✅ SQL wildcard characters are special symbols used inside the LIKE operator to search for patterns in text columns rather than exact values.

✅ They allow you to find rows where a column value starts with, ends with, contains, or matches a specific pattern of characters.

✅ The two main wildcards available in all SQL databases are % and _.

✅ Additional wildcards [ ] and [^ ] are supported in SQL Server and MS Access only — not in MySQL or PostgreSQL.

✅ Sample Employees Table – used in all examples below:-

✅ SQL LIKE Syntax with Wildcards

SELECT column1, column2, ...
FROM table_name
WHERE column_name LIKE 'pattern';

✅ LIKE:- Operator that enables pattern matching using wildcard characters.

✅ 'pattern':- A text pattern enclosed in single quotes containing wildcards and/or literal characters.

✅ NOT LIKE Syntax (exclude pattern):-

SELECT column1, column2, ...
FROM table_name
WHERE column_name NOT LIKE 'pattern';

✅ SQL Wildcard Characters – Complete Reference Table

✅ Example 1 – % Prefix: Names Starting with 'A'

Find all employees whose name starts with the letter 'A'. The % after A matches any characters following it:

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE 'A%';

✅ Result Show:-

✅ Example 2 – % Suffix: Names Ending with 'n'

Find all employees whose name ends with the letter 'n'. The % before n matches any characters before it:

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE '%n';

✅ Result Show:-

✅ Example 3 – % Both Sides: Names Containing 'ou'

Find all employees whose name contains 'ou' anywhere — beginning, middle, or end:

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE '%ou%';

✅ Result Show:-

✅ Example 4 – _ Wildcard: Find Names with Exactly 5 Characters

Find all employees whose name is exactly 5 characters long. Each _ represents exactly one character:

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE '_____';

(5 underscores = exactly 5 characters)

✅ Result Show:-

✅ Example 5 – _ Wildcard: Match Specific Character Position

Find all employees whose name has any first character, followed by exactly 'nni':

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE '_nni';

✅ Result Show:-

✅ Example – 4-letter name starting with 'A', ending with 'I':-

SELECT * FROM Employees
WHERE Name LIKE 'A__I';

✅ Result Show:-

✅ Example 6 – Combined % and _ Pattern

Combine % and _ in one pattern. Find all employees whose name starts with 'P', has at least one character in the middle, and ends with 'A':

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE 'P%A';

✅ Result Show:-

✅ Example – Names with exactly 6 characters starting with 'P':-

SELECT * FROM Employees
WHERE Name LIKE 'P_____';

(P + 5 underscores = exactly 6 characters starting with P)

✅ Result Show:-

✅ Example 7 – NOT LIKE: Exclude a Pattern

NOT LIKE returns all rows where the column value does NOT match the specified pattern — the opposite of LIKE:

✅ Example – Names NOT starting with 'A':-

SELECT * FROM Employees
WHERE Name NOT LIKE 'A%';

✅ Result Show:-

✅ Example – Names NOT containing 'ou':-

SELECT * FROM Employees
WHERE Name NOT LIKE '%ou%';

✅ Result Show:-

✅ Example 8 – LIKE Combined with AND (Name + City Pattern)

Find employees whose name starts with 'P' AND whose city starts with 'P':

✅ SELECT Query:-

SELECT * FROM Employees
WHERE Name LIKE 'P%'
  AND City LIKE 'P%';

✅ Result Show:-

✅ Example – Find IT employees with 4-letter names:-

SELECT * FROM Employees
WHERE Department = 'IT'
  AND Name LIKE '____';

(4 underscores = exactly 4 characters)

✅ Result Show:-

✅ LIKE vs = (Equals) Comparison

✅ Key Points to Remember

✅ % matches zero or more characters — can be placed before, after, or on both sides of a literal: 'A%', '%n', '%ou%'.

✅ _ matches exactly one character — use multiple underscores to match exact-length values: '_____' = exactly 5 chars.

✅ LIKE always works with single quotes — the pattern must be enclosed in single quotes: LIKE 'A%', not LIKE A%.

✅ Combine % and _ for complex patterns — 'A__I' = 4-char name starting with A ending with I.

✅ NOT LIKE excludes the pattern — the opposite of LIKE, returns rows that do NOT match.

✅ [ ] and [^ ] only work in SQL Server / MS Access — not supported in MySQL or PostgreSQL.

✅ Leading % causes full table scan — avoid '%value' or '%value%' on large tables for performance-critical queries.

✅ NULL columns never match LIKE — rows with NULL in the searched column are always excluded.

✅ Case sensitivity depends on database — MySQL is case-insensitive by default; PostgreSQL is case-sensitive (use ILIKE for case-insensitive).

✅ Common SQL Wildcard Mistakes to Avoid