1. Helia / Martti Laiho, 1998-2000 JDBC Java Database Connection

2. Helia / Martti Laiho, 1998-2000 Notes on JDBC - Java Database Connection Class Library: java.sql.* Literature/sources: SunSoft: http://java.sun.com/products/jdbc JDBC Specification jdk1.3/docs/guide/jdbc/ JDBC Guide: Getting Started Seth White & al: JDBC TM API Tutorial and Reference, 2nd ed Horstmann & Cornell: Core JAVA Volume II Chapter 4 Orfali & Harkey: Client/Server Programming with JAVA and CORBA Siple: The Complete Guide to JAVA Database Programming, McGraw-Hill SOLID JDBC: sj23win.zip SOLID JDBC Driver Programmer’s Guide Melton & Eisenberg: Understanding SQL and Java Together

3. Helia / Martti Laiho, 1998-2000 JDBC 1.0 API Designed by JavaSoft based on ISO SQL/CLI and Microsoft ODBC API provided in java.sql package 4 types of JDBC Driver implementation

4. Helia / Martti Laiho, 1998-2000 Types of JDBC Implementations Java appl JDBC-ODBC bridge ODBC driver DBMS Java appl JDBC driver Native db-library DBMS Java appl JDBC server gateway DBMS Java appl DBMS Proprietary protocol Proprietary protocol JDBC driver JDBC driver DBMS- independent protocol DBMS- specific protocol Type 1 Type 2Type 3Type 4 - Melton & Eisenberg - Oracle JDBC/OCI - Oracle Thin JDBC - Sybase jConnect - Solid

5. Helia / Martti Laiho, 1998-2000 SQL and Java data types SQL data type: INT[EGER] SMALLINT NUMERIC (m, n) DECIMAL (m, n) DEC (m, n) FLOAT (n) REAL DOUBLE CHAR[ACTER] (n) VARCHAR (n) DATE TIME TIMESTAMP Java data type: int short java.sql.BigDecimal double float double String java.sql.Date java.sql.Time java.sql.Timestamp

6. Helia / Martti Laiho, 1998-2000 Java.sql - Interfaces / Methods... getMetaData() setAutoCommit(b) setTransaction Isolation(level) createStatement() prepareStatement(sql) prepareCall(sql) commit() rollback() close() setCursorName(s) executeQuery(sql) executeUpdate(sql) cancel() close() getMetaData() findColumn(name) next() getInt(col) getShort(col) getNumeric(col) getDouble(col) getFloat(col) getString(col) getDate(col) getTime(col) getTimestamp(col) wasNull() setText(s) append(s) close() SQLException getSQLState() getErrorCode() getNextExcetion() Driver Connection Statement ResultSetResultSetMetaData getColumnCount() getColumnName(i) getColumnLabel(i) getColumnDisplaySize(i) DatabaseMetaData getTables(…) … PreparedStatement … setXxxx(n, hvar) clearParameters() getConnection (url, user, psw) DriverManager Class CallableStatement registerOutputParameter execute()... getConnection (url, user, psw) DataSource

7. Helia / Martti Laiho, 1998-2000 SQL Query String s; float n;... String query = "SELECT COF_NAME, PRICE FROM COFFEES"; ResultSet rs = stmt.executeQuery(query); while (rs.next()) { s = rs.getString("COF_NAME"); n = rs.getFloat("PRICE"); System.out.println(s + " " + n); } rs.close; COF_NAME PRICE snsn rs.next() rs.getString() rs.getFloat()

8. Helia / Martti Laiho, 1998-2000 SQLQuery Sequence Diagram Client DriverManager Connection Statement ResultSet getConnection createStatement next getString getInt... close executeQuery adapted from Orfali & Harkey { [ Until next returns false ] }

9. Helia / Martti Laiho, 1998-2000 Invoking a Stored Procedure Client DriverManager Connection Callable Statement Callable Statement getConnection prepareCall getString getInt... close execute... adapted from Orfali & Harkey parameters marked in the procedures call by ? placeholders are identified by the corresponding order numbers 1, 2,.. of the placeholders registerOutputParameter

10. Helia / Martti Laiho, 1998-2000 JDBC Escape Syntax call{call proc (arg1, …) } ?=call{?= call proc (arg1, …) } d{d ‘yyyy-mm-dd’} escape{escape ‘%’} fn{fn function (arg1, …) } oj{oj outer-join } t{t ‘hh:mm:ss’} ts{ts ‘yyyy-mm-dd hh:mm:ss.fffff’}

11. Helia / Martti Laiho, 1998-2000 Transactions Default: AutoCommit Isolation Levels: 0TRANSACTION_NONE 1TRANSACTION_READ_UNCOMMITTED 2TRANSACTION_READ_COMMITTED 3TRANSACTION_REAPEATABLE_READ 4TRANSACTION_SERIALIZABLE Methods: con.setAutoCommit(false); level = con.getTransactionIsolation(); con.setTransactionIsolation(level); con.commit(); con.rollback();

12. Helia / Martti Laiho, 1998-2000 Exception handling try { jdbc method call... } catch (SQLException ex) { System.out.println (”\nSQLException:"); while (ex != null) { System.out.println (”SQLState: "+ex.getSQLState()); System.out.println (”Message: "+ ex.getMessage()); System.out.println (”Vendor: "+ ex.getErrorCode()); ex = ex.getNextException(); } catch (java.lang.Exception ex) { System.out.println("Exception: " + ex); ex.printStackTrace (); } - adapted from Core JAVA Vol II ch 4 p 206

13. Helia / Martti Laiho, 1998-2000 JDBC 2.0 API JDBC 2.0 Core API (java.sql) –Scrollable ResultSet –Updating by ResultSet –Batch Updates –New SQL-99 datatypes JDBC 2.0 Standard Extension API (javax.sql)

14. Helia / Martti Laiho, 1998-2000 Scrollable ResultSet Resultset types –TYPE_FORWARD_ONLY (~JDBC 1.0) –TYPE_SCROLL_INSENSITIVE –TYPE_SCROLL_SENSITIVE Methods –beforeFirst() (initially) –first() –next() ( JDBC 1.0) –previous() –last() –afterLast() –absolute (n | -n) –relative (n | -n) –getRow() –isFirst(), isLast(), isBeforeFirst(), isAfterLast() –moveToInsertRow(), moveToCurrentRow()

15. Helia / Martti Laiho, 1998-2000 Updatable ResultSet Updatable –CONCUR_READ_ONLY (~JDBC 1.0) –CONCUR_UPDATABLE Methods –updateXXX(column, value) –… –updateRow() or cancelRowUpdates()

16. Helia / Martti Laiho, 1998-2000 Inserting a new row InsertRow processing: –moveToInsertRow() –updateXXX(, ) …. –insertRow() –moveToCurrentRow() updateable row “Current row” “InsertRow buffer” moveToInsertRow() moveToCurrentRow() InsertRow() ResultSet:

17. Helia / Martti Laiho, 1998-2000 Deleting a Row Positioning in the ResultSet and deleting: – –deleteRow() Note: –drivers handle deletions differently

18. Helia / Martti Laiho, 1998-2000 Refreshing the row Applies only to Cursor type: –TYPE_SCROLL_SENSITIVE method –refreshRow()

19. Helia / Martti Laiho, 1998-2000 Batch Updates Methods –addBatch(“….”) –… –executeBatch(); BatchUpdateException

20. Helia / Martti Laiho, 1998-2000 SQL-1999 Datatypes BLOB - binary large objects CLOB - character large objects SQL Array - of any SQL scalar datatype SQL structured type - User Defined Type UDT SQL REF - identifier

21. Helia / Martti Laiho, 1998-2000 JDBC 2.0 Standard Extension API JDBC 2.0 Standard Extension API i.e. Optional Package API –in javax.sql –JavaBeans: Rowsets –JNDI for naming and directory interface –Connection Pooling –Distributed Transactions: 2PC by Java Transaction API (JTA)