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.. _`HSQLDB`: http://www.hsqldb.org/
.. _`HSQLDB SQL manual`: http://www.hsqldb.org/doc/guide/ch09.html

HsqlDB
======

DdlUtils supports the `HSQLDB`_ database, version 1.7.2 or newer. SQL Documentation for
HSQLDB can be found in the distribution, and for the newest version in the
`HSQLDB SQL manual`_.

Constraints
-----------

Platform identifier
  ``HsqlDb``

Recognized JDBC drivers
  ``org.hsqldb.jdbcDriver``

Recognized JDBC sub protocols
  ``jdbc:hsqldb``

Supports SQL comments
  yes

Supports delimited identifiers
  yes

Maximum identifier length
  unlimited

Supports default values for ``LONG`` types
  yes

Supports non-unique indices
  yes

Supports non-primary key columns as identity columns
  no

Allows ``INSERT``/``UPDATE`` statements to set values for identity columns
  yes

DdlUtils uses sequences for identity columns
  no

DdlUtils can read back the auto-generated value of an identity column
  yes

DdlUtils can create a database via JDBC
  no

DdlUtils can drop a database via JDBC
  no

Datatypes
---------

+-----------------+--------------------------------+---------------------------------------------+
|JDBC Type        |Database Type                   |Additional comments                          |
+=================+================================+=============================================+
|``ARRAY``        |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``BIGINT``       |``BIGINT``                      |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``BINARY``       |``BINARY``                      |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``BIT``          |``BOOLEAN``                     |Will be read back as ``BOOLEAN``             |
+-----------------+--------------------------------+---------------------------------------------+
|``BLOB``         |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``BOOLEAN``      |``BOOLEAN``                     |``BOOLEAN`` is supported natively by Hsqldb  |
|                 |                                |only since version 1.7.2                     |
+-----------------+--------------------------------+---------------------------------------------+
|``CHAR``         |``CHAR``                        |The size is optional, by default Hsqldb does |
|                 |                                |not enforce it                               |
+-----------------+--------------------------------+---------------------------------------------+
|``CLOB``         |``LONGVARCHAR``                 |Will be read back as ``LONGVARCHAR``         |
+-----------------+--------------------------------+---------------------------------------------+
|``DATALINK``     |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``DATE``         |``DATE``                        |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``DECIMAL``      |``DECIMAL``                     |Precision and scale are ignored by Hsqldb, as|
|                 |                                |it uses unlimited precision and scale        |
+-----------------+--------------------------------+---------------------------------------------+
|``DISTINCT``     |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``DOUBLE``       |``DOUBLE``                      |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``FLOAT``        |``DOUBLE``                      |Will be read back as ``DOUBLE``              |
+-----------------+--------------------------------+---------------------------------------------+
|``INTEGER``      |``INTEGER``                     |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``JAVA_OBJECT``  |``OBJECT``                      |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``LONGVARBINARY``|``LONGVARBINARY``               |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``LONGVARCHAR``  |``LONGVARCHAR``                 |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``NULL``         |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``NUMERIC``      |``NUMERIC``                     |Precision and scale are ignored by Hsqldb, as|
|                 |                                |it uses unlimited precision and scale        |
+-----------------+--------------------------------+---------------------------------------------+
|``OTHER``        |``OTHER``                       |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``REAL``         |``REAL``                        |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``REF``          |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``SMALLINT``     |``SMALLINT``                    |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``STRUCT``       |``LONGVARBINARY``               |Will be read back as ``LONGVARBINARY``       |
+-----------------+--------------------------------+---------------------------------------------+
|``TIME``         |``TIME``                        |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``TIMESTAMP``    |``TIMESTAMP``                   |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``TINYINT``      |``SMALLINT``                    |JDBC's ``TINYINT`` requires a value range of |
|                 |                                |-255 to 255, but HsqlDb's is only -128 to    |
|                 |                                |127. Will be read back as ``SMALLINT``       |
+-----------------+--------------------------------+---------------------------------------------+
|``VARBINARY``    |``VARBINARY``                   |                                             |
+-----------------+--------------------------------+---------------------------------------------+
|``VARCHAR``      |``VARCHAR``                     |The size is optional, by default Hsqldb does |
|                 |                                |not enforce it                               |
+-----------------+--------------------------------+---------------------------------------------+