databasemetadata.java

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     * <li>
     * <B>FK_NAME</B> String => foreign key identifier (may be null)
     * </li>
     * <li>
     * <B>PK_NAME</B> String => primary key identifier (may be null)
     * </li>
     * </ol>
     * </p>
     *
     * @param catalog a catalog name; "" retrieves those without a catalog
     * @param schema a schema name pattern; "" retrieves those without a schema
     * @param table a table name
     *
     * @return ResultSet each row is a foreign key column description
     *
     * @throws SQLException if a database access error occurs
     *
     * @see #getImportedKeys
     */
    public java.sql.ResultSet getExportedKeys(String catalog, String schema,
        String table) throws SQLException {
        if (table == null) {
            throw new SQLException("Table not specified.",
                SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
        }

        Field[] fields = new Field[14];
        fields[0] = new Field("", "PKTABLE_CAT", Types.CHAR, 255);
        fields[1] = new Field("", "PKTABLE_SCHEM", Types.CHAR, 0);
        fields[2] = new Field("", "PKTABLE_NAME", Types.CHAR, 255);
        fields[3] = new Field("", "PKCOLUMN_NAME", Types.CHAR, 32);
        fields[4] = new Field("", "FKTABLE_CAT", Types.CHAR, 255);
        fields[5] = new Field("", "FKTABLE_SCHEM", Types.CHAR, 0);
        fields[6] = new Field("", "FKTABLE_NAME", Types.CHAR, 255);
        fields[7] = new Field("", "FKCOLUMN_NAME", Types.CHAR, 32);
        fields[8] = new Field("", "KEY_SEQ", Types.SMALLINT, 2);
        fields[9] = new Field("", "UPDATE_RULE", Types.SMALLINT, 2);
        fields[10] = new Field("", "DELETE_RULE", Types.SMALLINT, 2);
        fields[11] = new Field("", "FK_NAME", Types.CHAR, 255);
        fields[12] = new Field("", "PK_NAME", Types.CHAR, 0);
        fields[13] = new Field("", "DEFERRABILITY", Types.INTEGER, 2);

        if (this.conn.versionMeetsMinimum(3, 23, 0)) {
            Statement stmt = null;
            ResultSet fkresults = null;

            try {
                stmt = this.conn.createStatement();
                stmt.setEscapeProcessing(false);

                /*
                 * Get foreign key information for table
                 */
                if (this.conn.versionMeetsMinimum(3, 23, 50)) {
                    // we can use 'SHOW CREATE TABLE'
                    String db = this.database;

                    if (catalog != null) {
                        if (!catalog.equals("")) {
                            db = catalog;
                        }
                    }

                    fkresults = extractForeignKeyFromCreateTable(this.conn,
                            this, db, null);
                } else {
                    String databasePart = "";

                    if (catalog != null) {
                        if (!catalog.equals("")) {
                            databasePart = " FROM " + catalog;
                        }
                    } else {
                        databasePart = " FROM " + this.database;
                    }

                    fkresults = stmt.executeQuery("show table status " +
                            databasePart);
                }

                // lower-case table name might be turned on
                String tableNameWithCase = getTableNameWithCase(table);

                /*
                * Parse imported foreign key information
                */
                ArrayList tuples = new ArrayList();

                while (fkresults.next()) {
                    String tableType = fkresults.getString("Type");

                    if ((tableType != null) &&
                            (tableType.equalsIgnoreCase("innodb") ||
                            tableType.equalsIgnoreCase(SUPPORTS_FK))) {
                        String comment = fkresults.getString("Comment").trim();

                        if (comment != null) {
                            StringTokenizer commentTokens = new StringTokenizer(comment,
                                    ";", false);

                            if (commentTokens.hasMoreTokens()) {
                                commentTokens.nextToken(); // Skip InnoDB comment

                                while (commentTokens.hasMoreTokens()) {
                                    String keys = commentTokens.nextToken();
                                    getExportKeyResults(catalog,
                                        tableNameWithCase, keys, tuples,
                                        fkresults.getString("Name"));
                                }
                            }
                        }
                    }
                }

                return buildResultSet(fields, tuples);
            } finally {
                if (fkresults != null) {
                    try {
                        fkresults.close();
                    } catch (SQLException sqlEx) {
                        AssertionFailedException.shouldNotHappen(sqlEx);
                    }

                    fkresults = null;
                }

                if (stmt != null) {
                    try {
                        stmt.close();
                    } catch (Exception ex) {
                        AssertionFailedException.shouldNotHappen(ex);
                    }

                    stmt = null;
                }
            }
        }

        return buildResultSet(fields, new ArrayList());
    }

    /**
     * Get all the "extra" characters that can be used in unquoted identifier
     * names (those beyond a-z, 0-9 and _).
     *
     * @return the string containing the extra characters
     *
     * @throws SQLException DOCUMENT ME!
     */
    public String getExtraNameCharacters() throws SQLException {
        return "#@";
    }

    /**
     * What's the string used to quote SQL identifiers? This returns a space "
     * " if identifier quoting isn't supported. A JDBC compliant driver always
     * uses a double quote character.
     *
     * @return the quoting string
     *
     * @throws SQLException DOCUMENT ME!
     */
    public String getIdentifierQuoteString() throws SQLException {
        if (this.conn.supportsQuotedIdentifiers()) {
            if (!this.conn.useAnsiQuotedIdentifiers()) {
                return "`";
            }

            return "\"";
        }

        return " ";
    }

    /**
     * Get a description of the primary key columns that are referenced by a
     * table's foreign key columns (the primary keys imported by a table).
     * They are ordered by PKTABLE_CAT, PKTABLE_SCHEM, PKTABLE_NAME, and
     * KEY_SEQ.
     *
     * <P>
     * Each primary key column description has the following columns:
     *
     * <OL>
     * <li>
     * <B>PKTABLE_CAT</B> String => primary key table catalog being imported
     * (may be null)
     * </li>
     * <li>
     * <B>PKTABLE_SCHEM</B> String => primary key table schema being imported
     * (may be null)
     * </li>
     * <li>
     * <B>PKTABLE_NAME</B> String => primary key table name being imported
     * </li>
     * <li>
     * <B>PKCOLUMN_NAME</B> String => primary key column name being imported
     * </li>
     * <li>
     * <B>FKTABLE_CAT</B> String => foreign key table catalog (may be null)
     * </li>
     * <li>
     * <B>FKTABLE_SCHEM</B> String => foreign key table schema (may be null)
     * </li>
     * <li>
     * <B>FKTABLE_NAME</B> String => foreign key table name
     * </li>
     * <li>
     * <B>FKCOLUMN_NAME</B> String => foreign key column name
     * </li>
     * <li>
     * <B>KEY_SEQ</B> short => sequence number within foreign key
     * </li>
     * <li>
     * <B>UPDATE_RULE</B> short => What happens to foreign key when primary is
     * updated:
     *
     * <UL>
     * <li>
     * importedKeyCascade - change imported key to agree with primary key
     * update
     * </li>
     * <li>
     * importedKeyRestrict - do not allow update of primary key if it has been
     * imported
     * </li>
     * <li>
     * importedKeySetNull - change imported key to NULL if its primary key has
     * been updated
     * </li>
     * </ul>
     *
     * </li>
     * <li>
     * <B>DELETE_RULE</B> short => What happens to the foreign key when primary
     * is deleted.
     *
     * <UL>
     * <li>
     * importedKeyCascade - delete rows that import a deleted key
     * </li>
     * <li>
     * importedKeyRestrict - do not allow delete of primary key if it has been
     * imported
     * </li>
     * <li>
     * importedKeySetNull - change imported key to NULL if its primary key has
     * been deleted
     * </li>
     * </ul>
     *
     * </li>
     * <li>
     * <B>FK_NAME</B> String => foreign key name (may be null)
     * </li>
     * <li>
     * <B>PK_NAME</B> String => primary key name (may be null)
     * </li>
     * </ol>
     * </p>
     *
     * @param catalog a catalog name; "" retrieves those without a catalog
     * @param schema a schema name pattern; "" retrieves those without a schema
     * @param table a table name
     *
     * @return ResultSet each row is a primary key column description
     *
     * @throws SQLException if a database access error occurs
     *
     * @see #getExportedKeys
     */
    public java.sql.ResultSet getImportedKeys(String catalog, String schema,
        String table) throws SQLException {
        if (table == null) {
            throw new SQLException("Table not specified.",
                SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
        }

        Field[] fields = new Field[14];
        fields[0] = new Field("", "PKTABLE_CAT", Types.CHAR, 255);
        fields[1] = new Field("", "PKTABLE_SCHEM", Types.CHAR, 0);
        fields[2] = new Field("", "PKTABLE_NAME", Types.CHAR, 255);
        fields[3] = new Field("", "PKCOLUMN_NAME", Types.CHAR, 32);
        fields[4] = new Field("", "FKTABLE_CAT", Types.CHAR, 255);
        fields[5] = new Field("", "FKTABLE_SCHEM", Types.CHAR, 0);
        fields[6] = new Field("", "FKTABLE_NAME", Types.CHAR, 255);
        fields[7] = new Field("", "FKCOLUMN_NAME", Types.CHAR, 32);
        fields[8] = new Field("", "KEY_SEQ", Types.SMALLINT, 2);
        fields[9] = new Field("", "UPDATE_RULE", Types.SMALLINT, 2);
        fields[10] = new Field("", "DELETE_RULE", Types.SMALLINT, 2);
        fields[11] = new Field("", "FK_NAME", Types.CHAR, 255);
        fields[12] = new Field("", "PK_NAME", Types.CHAR, 0);
        fields[13] = new Field("", "DEFERRABILITY", Types.INTEGER, 2);

        if (this.conn.versionMeetsMinimum(3, 23, 0)) {
            Statement stmt = null;
            ResultSet fkresults = null;

            try {
                stmt = this.conn.createStatement();
                stmt.setEscapeProcessing(false);

                /*
                 * Get foreign key information for table
                 */
                if (this.conn.versionMeetsMinimum(3, 23, 50)) {
                    // we can use 'SHOW CREATE TABLE'
                    String db = this.database;

                    if (catalog != null) {
                        if (!catalog.equals("")) {
                            db = catalog;
                        }
                    }

                    fkresults = extractForeignKeyFromCreateTable(this.conn,
                            this, db, table);
                } else {
                    String databasePart = "";

                    if (catalog != null) {
                        if (!catalog.equals("")) {
                            databasePart = " FROM " + catalog;
                        }
                    } else {
                        databasePart = " FROM " + this.database;
                    }

                    fkresults = stmt.executeQuery("show table status " +
                            databasePart + " like '" + table + "'");
                }

                /*
                * Parse imported foreign key information
                */
                ArrayList tuples = new ArrayList();

                while (fkresults.next()) {
                    String tableType = fkresults.getString("Type");

                    if ((tableType != null) &&
                            (tableType.equalsIgnoreCase("innodb") ||
                            tableType.equalsIgnoreCase(SUPPORTS_FK))) {
                        String comment = fkresults.getString("Comment").trim();

                        if (comment != null) {
                            StringTokenizer commentTokens = new StringTokenizer(comment,
                                    ";", false);

                            if (commentTokens.hasMoreTokens()) {
                                commentTokens.nextToken(); // Skip InnoDB comment

                                while (commentTokens.hasMoreTokens()) {
                                    String keys = commentTokens.nextToken();
                                    getImportKeyResults(catalog, table, keys,
                                        tuples);
                                }
                            }
                        }
                    }
                }

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