protected void disableCheckAndUniqueConstraints() {
        Connection connection = null;
        Statement queryStatement = null;
        Statement alterStatement = null;
        ResultSet resultSet = null;
        try {
            connection = getSQLHandler().getDataSource().getConnection();
            queryStatement = connection.createStatement();
            alterStatement = connection.createStatement();

            resultSet = queryStatement.executeQuery("select TABLE_NAME, "
              + "CONSTRAINT_NAME from INFORMATION_SCHEMA.CONSTRAINTS where "
              + "CONSTRAINT_TYPE IN ('CHECK', 'UNIQUE') AND CONSTRAINT_SCHEMA "
              + "= '" + getSchemaName() + "'");
            while (resultSet.next()) {
                String tableName = resultSet.getString("TABLE_NAME");
                String constraintName = resultSet.getString("CONSTRAINT_NAME");
                alterStatement.executeUpdate("alter table "
                  + qualified(tableName) + " drop constraint "
                  + quoted(constraintName));
            }
        } catch (Exception e) {
            throw new UnitilsException("Error while disabling check and unique "
              + "constraints on schema " + getSchemaName(), e);
        } finally {
            closeQuietly(queryStatement);
            closeQuietly(connection, alterStatement, resultSet);
        }
    }
Disables all check and unique constraints on all tables in the schema
spock-unitils/src/test/java/org/unitils/core/dbsupport/H2DbSupport.java