Supported Constraint Mapping

Constraint	SQLAlchemy expression
gt	column > value
ge	column >= value
lt	column < value
le	column <= value
min_length	func.length(column) >= value
max_length	func.length(column) <= value
multiple_of	column % value == 0
Literal[...]	column.in_(...)
Enum	column.in_(member values)
pattern	IR (PatternSpec); translators via plugins / custom registry
type_check	IR (TypeSpec) when emit_type_checks=True; translators via plugins

Dialect markers (sqlrules.markers)

Marker	IR operator	Typical plugin translation
JsonContains	json_contains	JSONB / JSON containment
JsonHasKey	json_has_key	JSON key existence
ArrayContains	array_contains	PostgreSQL array containment
ArrayOverlap	array_overlap	PostgreSQL array overlap
RangeContains	range_contains	PostgreSQL range @>
RangeOverlap	range_overlap	PostgreSQL range &&
FullTextMatch	fulltext_match	MySQL MATCH ... AGAINST

Accepted input forms for portable constraints include Field(...), annotated_types primitives, Interval, Len, conint/constr, and StringConstraints (length attributes; pattern becomes PatternSpec IR).

Constraints without a deterministic SQL equivalent are rejected by default. See TYPE_SUPPORT.md and ERRORS.md.

To translate pattern, type_check, or markers, use a dialect plugin:

from sqlrules import Compiler, JsonContains
from sqlrules_postgresql import PostgresPlugin

compiler = Compiler(
    plugins=[PostgresPlugin()],
    dialect="postgresql",
    emit_type_checks=True,
)

from sqlrules.constraints import pattern_text
from sqlrules.translators import default_registry

registry = default_registry()
registry.register_constraint(
    "pattern",
    lambda c, col, ctx: col.op("~")(pattern_text(c.value)[0]),
    on_conflict="replace",
)
compiler = sqlrules.Compiler(registry=registry)