Interface BuiltInMetadata.UniqueKeys

All Superinterfaces:
Enclosing class:

public static interface BuiltInMetadata.UniqueKeys extends Metadata
Metadata about which combinations of columns are unique identifiers.
  • Field Details

  • Method Details

    • getUniqueKeys

      @Nullable Set<ImmutableBitSet> getUniqueKeys(boolean ignoreNulls)
      Determines the set of unique minimal keys for this expression. A key is represented as an ImmutableBitSet, where each bit position represents a 0-based output column ordinal.

      Nulls can be ignored if the relational expression has filtered out null values.

      ignoreNulls - if true, ignore null values when determining whether the keys are unique
      set of keys, or null if this information cannot be determined (whereas empty set indicates definitely no keys at all)