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SDIF Schema Comparator

The SDIFSchemaComparator compares SDIF database schemas for equivalence and compatibility based on configurable rules.

Basic Usage​

from satif_sdk.comparators import SDIFSchemaComparator
from satif_sdk import SDIFDatabase

# Get schemas from SDIF databases
db1 = SDIFDatabase("data1.sdif")
db2 = SDIFDatabase("data2.sdif")
schema1 = db1.get_schema()
schema2 = db2.get_schema()

# Compare schemas
comparator = SDIFSchemaComparator()
are_equivalent, differences = comparator.compare(schema1, schema2)

print(f"Schemas equivalent: {are_equivalent}")
for diff in differences:
    print(f"- {diff}")

Configuration​

Use SDIFSchemaConfig to customize comparison rules:

from sdif_db.schema import SDIFSchemaConfig

config = SDIFSchemaConfig(
    ignore_table_order=True,
    ignore_column_order=False,
    ignore_metadata=True
)

comparator = SDIFSchemaComparator(config=config)

Methods​

compare(schema1, schema2, verbose_diff_level=0)​

Compares two schemas for equivalence.

Parameters:

  • schema1, schema2: Schemas from SDIFDatabase.get_schema()
  • verbose_diff_level: Detail level of differences
    • 0: Human-readable summary (default)
    • 1: DeepDiff dictionary
    • 2+: Full DeepDiff object

Returns: (bool, differences) where differences format depends on verbose_diff_level

is_compatible_with(consumer_schema, producer_schema)​

Checks if producer schema satisfies consumer requirements (subset relationship).

Returns: bool - True if producer is compatible with consumer needs

Usage Examples​

Basic equivalence check:

are_equal, diffs = comparator.compare(schema1, schema2)

Detailed differences:

are_equal, diff_dict = comparator.compare(schema1, schema2, verbose_diff_level=1)

Compatibility check:

# Can producer satisfy consumer's requirements?
is_compatible = comparator.is_compatible_with(
    consumer_schema=required_schema,
    producer_schema=actual_schema
)

Custom configuration:

from sdif_db.schema import SDIFSchemaConfig

config = SDIFSchemaConfig(
    ignore_metadata=True,
    ignore_table_order=True
)
comparator = SDIFSchemaComparator(config)