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Hypersonic SQL is an open source Java database engine with a standard SQL and JDBC interface. It is available from Sourceforge.
uPortal ships with a HSQL database to be used for basic development and testing. HsqlDb is not suitable for qa or production environments.
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Edit /uPortal/uportal-impl/src/main/resources/properties/rdbm.properties and uncommment uncomment the lines for hsql Modify the URL, username and password as appropriate:
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