Identifier Case Sensitivity

KalamDB uses case-insensitive identifiers for table names, namespace names, and column names.

Behavior

All identifiers are normalized to lowercase on creation:

-- These all refer to the same table:
CREATE TABLE Users (...)
SELECT * FROM users
SELECT * FROM USERS

-- These all refer to the same column:
SELECT FirstName FROM users
SELECT firstname FROM users
SELECT FIRSTNAME FROM users

Comparison with Other Databases

Database	Unquoted Identifiers	Quoted Identifiers
KalamDB	Lowercase (case-insensitive)	N/A
PostgreSQL	Lowercase (case-insensitive)	Preserved (case-sensitive)
MySQL	OS-dependent	OS-dependent
SQL Standard	Uppercase	Preserved

Rationale

• Predictable: No OS-dependent behavior
• Simple: Users don't need to remember exact casing
• Compatible: Matches DataFusion's default behavior
• Portable: Queries work consistently across platforms