Package org.h2.constraint

Class ConstraintUnique

java.lang.Object
org.h2.engine.DbObject
org.h2.schema.SchemaObject
org.h2.constraint.Constraint
org.h2.constraint.ConstraintUnique
All Implemented Interfaces:
Comparable<Constraint>, HasSQL
public class ConstraintUnique extends Constraint
A unique constraint. This object always backed by a unique index.

  • Constructor Details

    • ConstraintUnique

      public ConstraintUnique(Schema schema, int id, String name, Table table, boolean primaryKey, IndexColumn[] indexColumns, Index index, boolean indexOwner, NullsDistinct nullsDistinct)
      Parameters:
      schema - constraint belongs to
      id - of the constraint
      name - of the constraint
      table - constraint belongs to
      primaryKey - true if primary key constraint
      indexColumns - used by this constraint
      index - the index
      indexOwner - true if the index is generated by the system and belongs to this constraint
      nullsDistinct - NULL handling mode

  • Method Details

    • getConstraintType

      public Constraint.Type getConstraintType()
      Description copied from class: Constraint
      The constraint type name
      Specified by:
      getConstraintType in class Constraint
      Returns:
      the name

    • getCreateSQLForCopy

      public String getCreateSQLForCopy(Table forTable, String quotedName)
      Description copied from class: DbObject
      Build a SQL statement to re-create the object, or to create a copy of the object with a different name or referencing a different table
      Overrides:
      getCreateSQLForCopy in class DbObject
      Parameters:
      forTable - the new table
      quotedName - the quoted name
      Returns:
      the SQL statement

    • getCreateSQLWithoutIndexes

      public String getCreateSQLWithoutIndexes()
      Description copied from class: Constraint
      Get the SQL statement to create this constraint.
      Specified by:
      getCreateSQLWithoutIndexes in class Constraint
      Returns:
      the SQL statement

    • getCreateSQL

      public String getCreateSQL()
      Description copied from class: DbObject
      Construct the CREATE ... SQL statement for this object.
      Specified by:
      getCreateSQL in class DbObject
      Returns:
      the SQL statement

    • getColumns

      public IndexColumn[] getColumns()

    • removeChildrenAndResources

      public void removeChildrenAndResources(SessionLocal session)
      Description copied from class: DbObject
      Delete all dependent children objects and resources of this object.
      Specified by:
      removeChildrenAndResources in class DbObject
      Parameters:
      session - the session

    • checkRow

      public void checkRow(SessionLocal session, Table t, Row oldRow, Row newRow)
      Description copied from class: Constraint
      Check if this row fulfils the constraint. This method throws an exception if not.
      Specified by:
      checkRow in class Constraint
      Parameters:
      session - the session
      t - the table
      oldRow - the old row
      newRow - the new row

    • usesIndex

      public boolean usesIndex(Index idx)
      Description copied from class: Constraint
      Check if this constraint needs the specified index.
      Specified by:
      usesIndex in class Constraint
      Parameters:
      idx - the index
      Returns:
      true if the index is used

    • setIndexOwner

      public void setIndexOwner(Index index)
      Description copied from class: Constraint
      This index is now the owner of the specified index.
      Specified by:
      setIndexOwner in class Constraint
      Parameters:
      index - the index

    • getReferencedColumns

      public HashSet<Column> getReferencedColumns(Table table)
      Description copied from class: Constraint
      Get all referenced columns.
      Specified by:
      getReferencedColumns in class Constraint
      Parameters:
      table - the table
      Returns:
      the set of referenced columns

    • isBefore

      public boolean isBefore()
      Description copied from class: Constraint
      Check if this constraint needs to be checked before updating the data.
      Specified by:
      isBefore in class Constraint
      Returns:
      true if it must be checked before updating

    • checkExistingData

      public void checkExistingData(SessionLocal session)
      Description copied from class: Constraint
      Check the existing data. This method is called if the constraint is added after data has been inserted into the table.
      Specified by:
      checkExistingData in class Constraint
      Parameters:
      session - the session

    • getIndex

      public Index getIndex()
      Description copied from class: Constraint
      Get the index of this constraint in the source table, or null if no index is used.
      Overrides:
      getIndex in class Constraint
      Returns:
      the index

    • rebuild

      public void rebuild()
      Description copied from class: Constraint
      This method is called after a related table has changed (the table was renamed, or columns have been renamed).
      Specified by:
      rebuild in class Constraint

    • getNullsDistinct

      public NullsDistinct getNullsDistinct()
      Returns:
      are nulls distinct