private static void checkIfTableExists(final Connection connection, final DatabaseTable table) throws SQLException { final StringBuilder sb = new StringBuilder(); sb.append("SELECT * FROM ").append(table.toString()).append(" WHERE " + KEY_COLUMN + " = '0'"); Statement statement = null; ResultSet resultSet = null; try { statement = connection.createStatement(); resultSet = statement.executeQuery(sb.toString()); } finally { close(statement); close(resultSet); } }
private static void close(final Statement statement) { if (statement != null) { try { statement.close(); } catch (SQLException e) { LOGGER.error("unexpected error during close statement object " + e.getMessage(), e); } } }
private static void initTable( final Connection connection, final DatabaseTable table, final DBConfiguration dbConfiguration) throws DatabaseException { try { checkIfTableExists(connection, table); LOGGER.trace("table " + table + " appears to exist"); } catch (SQLException e) { // assume error was due to table missing; { final StringBuilder sqlString = new StringBuilder(); sqlString.append("CREATE table ").append(table.toString()).append(" (").append("\n"); sqlString .append(" " + KEY_COLUMN + " ") .append(dbConfiguration.getColumnTypeKey()) .append("(") .append(KEY_COLUMN_LENGTH) .append(") NOT NULL PRIMARY KEY,") .append("\n"); sqlString .append(" " + VALUE_COLUMN + " ") .append(dbConfiguration.getColumnTypeValue()) .append(" "); sqlString.append("\n"); sqlString.append(")").append("\n"); LOGGER.trace( "attempting to execute the following sql statement:\n " + sqlString.toString()); Statement statement = null; try { statement = connection.createStatement(); statement.execute(sqlString.toString()); LOGGER.debug("created table " + table.toString()); } catch (SQLException ex) { LOGGER.error("error creating new table " + table.toString() + ": " + ex.getMessage()); } finally { close(statement); } } { final String indexName = table.toString() + "_IDX"; final StringBuilder sqlString = new StringBuilder(); sqlString.append("CREATE index ").append(indexName); sqlString.append(" ON ").append(table.toString()); sqlString.append(" (").append(KEY_COLUMN).append(")"); Statement statement = null; LOGGER.trace( "attempting to execute the following sql statement:\n " + sqlString.toString()); try { statement = connection.createStatement(); statement.execute(sqlString.toString()); LOGGER.debug("created index " + indexName); } catch (SQLException ex) { LOGGER.error("error creating new index " + indexName + ": " + ex.getMessage()); } finally { close(statement); } } } }