SYNTAX_ERROR ClickHouse error

This error usually means there's a syntax error in your SQL query. Check for missing keywords, incorrect punctuation, or malformed SQL statements.

The SYNTAX_ERROR in ClickHouse (and Tinybird) happens when there's a syntax error in your SQL query. This can occur due to missing keywords, incorrect punctuation, malformed statements, or using SQL syntax that isn't supported by ClickHouse.

What causes this error

You'll typically see it when:

  • Missing required keywords (SELECT, FROM, etc.)
  • Incorrect punctuation or brackets
  • Malformed SQL statements
  • Using unsupported SQL syntax
  • Missing or extra commas, parentheses, or quotes

Error messages point to the problem location. Check trailing commas after the last column in SELECT statements.

Example errors

Fails: missing FROM clause
SELECT user_id, event_type
Fails: missing closing parenthesis
SELECT * FROM events WHERE user_id = (SELECT id FROM users
Fails: incorrect punctuation
SELECT user_id, event_type, FROM events
Fails: malformed statement
SELECT * events WHERE user_id = 123

How to fix it

Add missing keywords

Include all required SQL keywords:

Fix: add missing FROM
SELECT user_id, event_type FROM events

Fix punctuation

Correct punctuation and brackets:

Fix: correct punctuation
SELECT user_id, event_type FROM events WHERE user_id = 123

Complete statements

Ensure all statements are complete:

Fix: complete statement
SELECT * FROM events WHERE user_id = (SELECT id FROM users)

Use proper ClickHouse syntax

Use syntax supported by ClickHouse:

Fix: use ClickHouse syntax
SELECT user_id, event_type FROM events LIMIT 10

Common patterns and solutions

Basic SELECT statements

Correct SELECT statement syntax:

Basic SELECT
SELECT user_id, event_type FROM events
SELECT * FROM events WHERE user_id = 123
SELECT user_id, COUNT(*) FROM events GROUP BY user_id

JOIN statements

Correct JOIN syntax:

JOIN syntax
SELECT u.id, e.event_type 
FROM users u 
JOIN events e ON u.id = e.user_id

Subquery syntax

Correct subquery syntax:

Subquery syntax
SELECT * FROM events 
WHERE user_id IN (SELECT id FROM users WHERE status = 'active')

INSERT statements

Correct INSERT syntax:

INSERT syntax
INSERT INTO events (user_id, event_type) VALUES (123, 'click')
INSERT INTO events SELECT user_id, event_type FROM source_table

Advanced solutions

Using CTEs (Common Table Expressions)

Correct CTE syntax:

CTE syntax
WITH user_events AS (
    SELECT user_id, COUNT(*) as event_count
    FROM events
    GROUP BY user_id
)
SELECT * FROM user_events WHERE event_count > 10

Using window functions

Correct window function syntax:

Window function syntax
SELECT user_id, event_type,
       ROW_NUMBER() OVER (PARTITION BY user_id ORDER BY timestamp) as row_num
FROM events

Using array functions

Correct array function syntax:

Array function syntax
SELECT user_id, has(tags, 'important') as has_important_tag
FROM events

Common syntax mistakes

Missing keywords

Wrong: missing FROM
SELECT user_id, event_type
Correct: with FROM
SELECT user_id, event_type FROM events

Incorrect punctuation

Wrong: extra comma
SELECT user_id, event_type, FROM events
Correct: no extra comma
SELECT user_id, event_type FROM events

Malformed WHERE clauses

Wrong: incomplete WHERE
SELECT * FROM events WHERE user_id =
Correct: complete WHERE
SELECT * FROM events WHERE user_id = 123

Incorrect JOIN syntax

Wrong: missing ON
SELECT * FROM users JOIN events
Correct: with ON clause
SELECT * FROM users JOIN events ON users.id = events.user_id

Tinybird-specific notes

In Tinybird, this error often occurs when:

  • Writing SQL in Pipes with syntax errors
  • Using unsupported SQL syntax in Materialized Views
  • Creating API endpoints with malformed queries
  • Using SQL from other database systems

To debug in Tinybird:

  1. Use the Query Builder to test SQL syntax
  2. Check for ClickHouse-specific syntax requirements
  3. Validate SQL in Pipe nodes before saving
  4. Use syntax highlighting in your editor

The UI syntax highlighter can help spot missing parentheses and other syntax issues.

Best practices

SQL writing

  • Use a SQL editor with syntax highlighting
  • Test queries with simple examples first
  • Break down complex queries into smaller parts
  • Use consistent formatting and indentation

Error prevention

  • Double-check all keywords and punctuation
  • Ensure all parentheses are properly closed
  • Verify table and column names exist
  • Test queries step by step

Debugging

  • Start with simple queries and build complexity
  • Use the Query Builder for syntax validation
  • Check ClickHouse documentation for syntax
  • Use proper SQL formatting tools

See also