Module binary 

Coercion rules for matching argument types for binary operators

Structs

BinaryTypeCoercer

Provides type information about a binary expression, coercing different input types into a sensible output type.

Functions

binary_numeric_coercion

Coerce lhs_type and rhs_type to a common type where both are numeric

binary_to_string_coercion

Coercion rules for binary (Binary/LargeBinary) to string (Utf8/LargeUtf8): If one argument is binary and the other is a string then coerce to string (e.g. for like)

comparison_coercion

Coerce lhs_type and rhs_type to a common type for comparison contexts — any context where two values are compared rather than unified. This includes binary comparison operators, IN lists, CASE/WHEN conditions, and BETWEEN.

decimal_coercion

Decimal coercion rules.

like_coercion

Coercion rules for like operations. This is a union of string coercion rules, dictionary coercion rules, and REE coercion rules Note: list_coercion is intentionally NOT included here because LIKE is a string pattern matching operation and is not supported for nested types (List, Struct, etc.)

regex_coercion

Coercion rules for regular expression comparison operations. This is a union of string coercion rules, dictionary coercion rules, and REE coercion rules.

string_coercion

Coercion rules for string view types (Utf8/LargeUtf8/Utf8View): If at least one argument is a string view, we coerce to string view based on the observation that StringArray to StringViewArray is cheap but not vice versa.

try_type_union_resolution

Handle type union resolution including struct type and others.

try_type_union_resolution_with_struct

type_union_coercion

Coerce lhs_type and rhs_type to a common type for type unification contexts — where two values must be brought to a common type but are not being compared. Examples: UNION, CASE THEN/ELSE branches, NVL2. For other contexts, comparison_coercion should typically be used instead.

type_union_resolution

Coerce dissimilar data types to a single data type. ARRAY literals, VALUES, COALESCE, and array concatenation are examples of contexts that use this function. See https://www.postgresql.org/docs/current/typeconv-union-case.html for more information. The rules in the document provide a clue, but adhering strictly to them doesn’t precisely align with the behavior of Postgres. Therefore, we’ve made slight adjustments to the rules to better match the behavior of both Postgres and DuckDB. For example, we expect adjusted decimal precision and scale when coercing decimal types.