Module org.cojen.tupl
Package org.cojen.tupl

Annotation Interface AlternateKey

@Documented @Retention(RUNTIME) @Target(TYPE) @Repeatable(Set.class) public @interface AlternateKey
Annotation which defines an alternate set of columns that uniquely identify a row instance. Row definitions aren't required to have any @AlternateKey annotations.

An alternate key is essentially the same as a secondary index, except with a uniqueness constraint applied. Attempting to insert a row with a conflicting alternate key causes a UniqueConstraintException to be thrown.

See Also:

  • Required Element Summary

    Required Elements
    Modifier and Type
    Required Element
    Description
    String[]
    value
    The set of column names within alternate key, whose ordering affects the natural ordering of the rows within the alternate key index.

  • Element Details

    • value

      String[] value
      The set of column names within alternate key, whose ordering affects the natural ordering of the rows within the alternate key index. Column names can be optionally prefixed with a '+' or '-' character to indicate ascending or descending order. By default, column order is ascending.