String Types

Singdata Lakehouse supports the following string types: CHAR, VARCHAR(n), and STRING.

Type Comparison

Type	Length	Description
CHAR(n)	Fixed length n	Lakehouse does not pad with spaces; strings exceeding the length are silently truncated; max 255 characters
VARCHAR(n)	Variable, max n	No space padding; max 1,048,576 characters
STRING	Variable, no limit	Recommended for large text; no length restriction

Selection Guide

Fixed-length codes (e.g., country codes, status codes): use CHAR
Fields with a length cap (e.g., usernames, email addresses): use VARCHAR(n)
Long text, JSON strings, fields with no length constraint: use STRING

⚠️ Note: All three types silently truncate when the declared length is exceeded — no error is raised. Validate length at the application layer before writing.

⚠️ Note: Lakehouse CHAR does not pad with spaces, which differs from standard SQL behavior. LENGTH(CAST('abc' AS CHAR(10))) returns 3, not 10.

Examples

-- CHAR: truncates on overflow, does not pad on underflow SELECT CAST('hello' AS CHAR(3)); -- 'hel' (truncated) SELECT length(CAST('hi' AS CHAR(5))); -- 2 (no space padding) -- VARCHAR: truncates on overflow SELECT CAST('hello world' AS VARCHAR(5)); -- 'hello' -- STRING: no length limit SELECT typeof('any length of text'); -- string

String Types

Type Comparison

Selection Guide

Examples

Related Documentation