PostgreSQL Error 2200G: Most Specific Type Mismatch
PostgreSQL error code 2200G (most_specific_type_mismatch) is a SQL-standard data exception that occurs when a value's type does not match the most specific (most derived) type expected in a context involving type hierarchies, XML schema types, or user-defined structured types. It most commonly appears when working with composite types, domain hierarchies, or XML processing functions where type inheritance or derivation is in play. While relatively rare in everyday CRUD operations, it can be a significant pain point in enterprise applications with complex type systems.
Top 3 Causes and Fixes
1. Composite or Domain Type Hierarchy Mismatch
When a function expects a specific domain or composite type but receives a parent/base type, PostgreSQL raises 2200G. Always cast explicitly to the most specific required type.
