Database Access With JDBC

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contains good explanation on jdbc, connection pooling and connection pooling using c3p0, mysql database software

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Database Access With JDBC

  1. 1. JDBC <br />
  2. 2. JDBC<br />Is an API spec. whose implementation comes in the form of jdbc drivers.<br />JDBC API :<br />java.sql.*<br />javax.sql.*<br />
  3. 3. JDBC Driver<br />Is a bridge s/w between java application and database s/w.<br />Is a java class that implements java.sql.Driver interface.<br />Why we use JDBC Driver?<br />
  4. 4. JDBC Architecture<br />Application<br />JDBC<br />Driver<br />Java code calls JDBC library<br />JDBC loads a driver<br />Driver talks to a particular database<br />Can have more than one driver -> more than one database<br />
  5. 5. JDBC Drivers<br />Type I: “Bridge”<br />Type II: “Native”<br />Type III: “Middleware”<br />Type IV: “Pure”<br />
  6. 6. Type 1 Driver (jdbc - odbc bridge driver )<br />Oracle<br />DB<br />Java App that uses JDBC API<br />Jdbc driver type1<br />ODBC Driver for Oracle<br />Vendor DB Library for Oracle<br />MS Access<br />ODBC Driver for MS-Access<br />Vendor DB Library for M S Access<br />
  7. 7. Type 1 Driver (Cont….)<br />Inbuilt driver of j2sdk s/w.<br />Suitable to interact with almost all the database s/w ’s<br />Driver performance is very poor.<br />Not suitable for internet programming and applet to database communication<br />
  8. 8. Type 2 Driver (Native API /Partly Java Driver)<br />Oracle<br />DB<br />Java App that uses JDBC API<br />Jdbc driver type2<br />Vendor DB Library for Oracle<br />MS Access<br />Vendor DB Library for M S Access<br />Jdbc driver type2<br />
  9. 9. Type 2 Driver (cont…)<br />Specific to each database s/w.<br />Significantly better performance than Type 1.<br />Odbc drivers presence is not mandatory.<br />Not suitable for large scale applications.<br />Not suitable for internet / applet programs<br />Every db requires a separate driver.<br />
  10. 10. Type 4 Driver (Native Protocol /All Java Driver)<br />Oracle<br />DB<br />Java App that uses JDBC API<br />Jdbc driver type4<br />MS Access<br />Jdbc driver type4<br />
  11. 11. Type 4 Driver (Native Protocol / All Java Driver)<br />Completely developed in java.<br />Can interact with db without having the support of odbc driver / vendor db library.<br />Platform independent.<br />Performance is good.<br />Applet and internet programming is possible<br />
  12. 12. Type 3 Driver ( Network Protocol Driver )<br />Java app manipulates DB data using con object<br />Java App<br />(Client App)<br />DB S/W<br />Interact using type 1,2,4 drivers<br />Gets object from conn pool using type 3<br />Application Server<br />JDBC CONNECTION POOL<br />Release connection object back to conn pool<br />con<br />con<br />con<br />Java App<br />(Client App)<br />con<br />
  13. 13. Type 3 Driver<br />Is not a driver<br />Its protocol<br />Contains rules required to establish communication between java application and connection pool<br />
  14. 14. JDBC Drivers (Fig.)<br />JDBC<br />Type I<br />“Bridge”<br />ODBC<br />ODBC<br />Driver<br />Type II<br />“Native”<br />CLI (.lib)<br />Middleware<br />Server<br />Type III<br />“Middleware”<br />Type IV<br />“Pure”<br />
  15. 15. Steps to develop java/jdbc App<br />java.sql<br />Classes<br />------------<br />Types<br />DriverManager<br />Date<br />TimeStamp<br />Interfaces <br />---------------<br />Connection<br />Statement<br />ResultSet<br />Driver<br />PreparedStatement<br />CallableStatement<br />
  16. 16. Steps to develop java/jdbc App<br />Load the JDBC Driver class and register with DriverManager.<br />Establish the connection with database s/w.<br />Prepare Statement object<br />Execute the query.<br />Get result and process the result<br />Close the connection.<br />
  17. 17. Loading & Registering a Driver<br />statically load driver<br />Class.forName(“sun.jdbc.odbc.JdbcOdbcDriver”);<br />
  18. 18. DriverManager<br />All JDBC Drivers will be registered and managed by DriverManager.<br />When a driver class is first loaded, it registers itself with the DriverManager<br />Therefore, to register a driver, just load it!<br />
  19. 19. Connection<br />A Connection represents a session with a specific database.<br />Establishing connection with db s/w is nothing but creating communication channel<br />Can have multiple connections to a database<br />Once task with connection is completed, close the connection.<br />
  20. 20. Obtaining a Connection<br />String url = "jdbc:odbc:datasource";<br />try {<br />Class.forName ("sun.jdbc.odbc.JdbcOdbcDriver");<br /> Connection con = DriverManager.getConnection(url);<br />}<br />catch (ClassNotFoundException e) <br /> { e.printStackTrace(); }<br />catch (SQLException e)<br /> { e.printStackTrace(); }<br />
  21. 21. Statement<br />Acts as a courier service to send queries to the db s/w.<br />A Statement object is used for executing a static SQL statement and obtaining the results produced by it.<br />
  22. 22. Statement Methods<br />ResultSetexecuteQuery(String) <br />Execute a SQL statement that returns a single ResultSet. <br />intexecuteUpdate(String) <br />Execute a SQL INSERT, UPDATE or DELETE statement. Returns the number of rows changed.<br />boolean execute(String) <br />Execute a SQL statement that may return multiple results. <br />What is the difference between execute(-) and executeQuery(-)?<br />
  23. 23. ResultSet<br />A ResultSet object is a java object which can store bunch of selected rows given by select query execution.<br />Only one ResultSet per Statement can be open at once.<br />The table rows are retrieved in sequence.<br />A ResultSet maintains a cursor pointing to its current row of data. <br />The 'next' method moves the cursor to the next row. <br />
  24. 24. ResultSet<br />Cursor<br />BFR<br /> ALR<br />
  25. 25. ResultSet Methods<br />boolean next() <br />activates the next row<br />the first call to next() activates the first row<br />returns false if there are no more rows <br />void close() <br />disposes of the ResultSet<br />allows you to re-use the Statement that created it<br />
  26. 26. ResultSet Methods<br />TypegetType(intcolumnIndex)<br />returns the given field as the given type<br />fields indexed starting at 1 (not 0)<br />TypegetType(String columnName)<br />same, but uses name of field<br />less efficient<br />
  27. 27. ResultSet Methods<br />String getString(int columnIndex) <br />boolean getBoolean(int columnIndex) <br />byte getByte(int columnIndex) <br />short getShort(int columnIndex) <br />int getInt(int columnIndex) <br />long getLong(int columnIndex) <br />float getFloat(int columnIndex) <br />double getDouble(int columnIndex) <br />Date getDate(int columnIndex) <br />Time getTime(int columnIndex) <br />Timestamp getTimestamp(int columnIndex) <br />
  28. 28. JDBC Object Classes<br />DriverManager<br />Loads, chooses drivers<br />Driver<br />connects to actual database<br />Connection<br />a series of SQL statements to and from the DB<br />Statement<br />a single SQL statement<br />ResultSet<br />the records returned from a Statement<br />
  29. 29. JDBC Class Usage<br />DriverManager<br />Driver<br />Connection<br />Statement<br />ResultSet<br />
  30. 30. Types of Statement Objects<br />Statement Object<br />PreparedStatement Object<br />CallableStatement Object.<br />Operations performed by Database Engine :<br />Parse<br />Execute<br />Fetch<br />2) Parse<br />3) Execute<br />4) Fetch<br />DB Engine<br />Send sql query<br />Java <br />App<br />
  31. 31. Limitations of Statement Object<br />DB s/w parses the same query multiple no. of times and executes, fetches the o/p .<br />Framing query for simple Statement object using variable is quite unnecessary.<br />Network traffic to the DB s/w is heavy since same query goes multiple no. of times to the DB s/w.<br />To overcome these problems use precompiled queries.<br />
  32. 32. PreparedStament Object<br />A query that goes and resides on the DB s/w without values by becoming parsed query is a precompiled query.<br />Precompiled queries will be parsed only once, but capable of executing multiple times with same or different values.<br />PreparedStatement object represents this precompiled query.<br />When to use Statement object and PreparedStatement object ?<br />
  33. 33. Steps to work with PreparedStatement<br />Prepare the query having positional parameters.<br />String query=“insert into item values(?,?,?,?)”;<br />Positional parameter indicates value to that query will be set afterwards.<br />Create PreparedStatement object.<br />PreparedStatementps=con.prepareStatement(query);<br />Set the values for positional paremeters using setType(-,-) methods.<br />ps.setInt(-,-), ps.setString(-,-)<br />This method makes query as a precompiled query<br />
  34. 34. Steps to work with PreparedStatement<br />Execute the query<br />int result = ps.executeUpdate();<br />For more executions repeat step 3 & 4.<br />Close PreparedStatement object<br />ps.close()<br />
  35. 35. CallableStatement<br />DB s/w can maintain the business logic in the form of PL/SQL procedures and functions.<br />To call PL/SQL procedures and functions from the java app , use CallableStatement.<br />Procedure is a subprogram that performs specific action.<br />A function is a subprogram that computes a value.<br /> Functions and procedures are structured alike, except that functions have a RETURN clause<br />
  36. 36. CallableStatement<br />A parameter of function or procedure can be ther in three modes :<br />in (default)<br />out <br />inout<br />Y=X*X X=X*X<br />in<br />inout<br />out<br />
  37. 37. Steps to work with CallableStatement Object<br />Create query calling procedure<br />String query= “{ call procedure_name(?,?)}”;<br />Create CallableStatement object<br />CallableStatementcs=con.prepareCall(query);<br />Register out parameters with jdbc types.<br />Jdbc types are bridge data types between java data types and db s/w data types.<br />cs.registerOutParameter(param_index,Types.INTEGER);<br />Set values for IN parameters using setType(-,-).<br />cs.setInt(parameter_index,value);<br />Represents procedure is available on the db s/w<br />
  38. 38. Steps to work with CallableStatement Object<br />Execute the procedure<br />boolean b= cs.execute();<br />Gather the result from OUT parameter using getType() method.<br />int result=cs.getType(column_index);<br />For more executions repeat steps 4 , 5, and 6.<br />Close the CallableStatement object.<br />cs.close();<br />
  39. 39. Mapping Java Types to SQL Types<br />SQL type Java Type<br />CHAR, VARCHAR, LONGVARCHAR String<br />NUMERIC, DECIMAL java.math.BigDecimal<br />BIT boolean<br />TINYINT byte<br />SMALLINT short<br />INTEGER int<br />BIGINT long<br />REAL float<br />FLOAT, DOUBLE double<br />BINARY, VARBINARY, LONGVARBINARY byte[]<br />DATE java.sql.Date<br />TIME java.sql.Time<br />TIMESTAMP java.sql.Timestamp<br />
  40. 40. Database Time<br />Java defines three classes to help<br />java.sql.Date<br />year, month, day<br />java.sql.Time<br />hours, minutes, seconds<br />java.sql.Timestamp<br />year, month, day, hours, minutes, seconds, nanoseconds<br />usually use this one<br />
  41. 41. Metadata with JDBC<br />Used to get information about tables, views, column names, column types, stored procedures, result sets, and databases.<br />You can use database metadata to<br />Discover database schema information.<br />Discover database users, tables, views, and stored procedures<br />Understand and analyze the result sets returned by SQL queries<br />Determine the signature of a specific stored procedure in the database.<br />Identify the primary/foreign keys for a given table<br />
  42. 42. Metadata in JDBC<br />DatabaseMetaData : Gives limitations & capabilities of underlying DB s/w.<br />Object of a class that implements java.sql.DatabaseMetaData interface.<br />DatabaseMetaDatadbmd=conn.getMetaData();<br />Invoke various methos on dbmd object to gather the details about the DB s/w pointed by Connection object.<br />ResultsetMetaData : Gives details about table that is represented by Resultset object.<br />Object of a class that implements java.sql.ResultsetMetaData interface.<br />ResultsetMetaDatarsmd=resltSetOb.getMetaData();<br />
  43. 43. Metadata in JDBC<br />ParameterMetaData : Gives details about place holders kept in queries.<br />Object of a class that implements java.sql.ParameterMetaData interface.<br />PreparedStatementpst=con.prepareStatement( “insert into items values(?,?,?,?)”);<br />ParameterMetaData d=pst.getParameterMetaData();<br />If any method invoked in DatabaseMetaData returns 0 or null , it means the driver is not capable of gathering certain information regarding DB s/w<br />Most of the drivers doesn’t support ParameterMetaData<br />
  44. 44. JDBC 2.0<br />Scrollable result set<br />Batch updates<br />Advanced data types<br />Blobs, objects, structured types<br />Rowsets<br />Persistent JavaBeans<br />JNDI<br />Connection Pooling<br />Distributed transactions via JTS<br />
  45. 45. Scrollable ResultSet<br />ResultSet Object<br />Non-Scrollable ResultSet Object<br />Scrollable ResultSet Object<br />ResultSet object that allows to access the records in one direction is non-scrollable.<br />ResultSet object that allows to access the records bi-directionally is called scrollable<br />
  46. 46. Scrollable ResultSet<br />JDBC 2.0 introduces scrollable results sets whose values can be read and updated if reading and updating is supported by the underlying database.<br /> With scrollable result sets, any row can be selected at random, and the result set can be traversed forwards and backwards.<br />One advantage to the new result set is you can update a set of matching rows without having to issue an additional executeUpdate call.<br />
  47. 47. Scrollable ResultSet<br />Both Statements and PreparedStatements have an additional constructor that accepts a scroll type and an update type parameter<br />The scroll type value can be one of the following values: <br />ResultSet.TYPE_FORWARD_ONLYDefault behavior in JDBC 1.0, application can only call next() on the result set. <br />ResultSet.SCROLL_SENSITIVEResultSet is fully navigable and updates are reflected in the result set as they occur. <br />ResultSet.SCROLL_INSENSITIVEResult set is fully navigable, but updates are only visible after the result set is closed. You need to create a new result set to see the results. <br />
  48. 48. Scrollable ResultSet<br />The update type parameter can be one of the following two values: <br />ResultSet.CONCUR_READ_ONLYThe result set is read only. <br />ResultSet.CONCUR_UPDATABLEThe result set can be updated. <br />You can verify that your database supports these types by calling :<br />con.getMetaData().supportsResultSetConcurrency() method <br />
  49. 49. Navigating the ResultSet<br />The fully scrollable result set returns a cursor which can be moved using simple commands.<br />By default the result set cursor points to the row before the first row of the result set.<br /> A call to next() retrieves the first result set row<br />beforeFirst(): Default position. Puts cursor before the first row of the result set. <br />first(): Puts cursor on the first row of the result set. <br />last(): Puts cursor before the last row of the result set. <br />afterLast() Puts cursor beyond last row of the result set. Calls to previous moves backwards through the ResultSet. <br />absolute(pos): Puts cursor at the row number position where absolute(1) is the first row and absolute(-1) is the last row. <br />relative(pos): Puts cursor at a row relative to its current position where relative(1) moves row cursor one row forward. <br />
  50. 50. Updatable ResultSet Object<br />If modifications done in the ResultSet object is reflecting in the DB table, then ResultSet object is called as Updatable ResultSet object.<br />We can perform insert, update, delete operations on the table without SQL statements.<br />You can update a value in a result set by calling the ResultSet.update<type> method on the row where the cursor is positioned<br />The update applies only to the result set until the call to rs.updateRow(), which updates the underlying database<br />Closing the result set before calling updateRow will lose any edits applied to the result set<br />
  51. 51. Updatable ResultSet Object<br />Inserting a new row uses the same update<type> methods<br />rs.moveToInsertRow is called before and rs.insertRow() is called after the fields have been initialized<br />You can delete the current row with a call to rs.deleteRow()<br />Is not suitable for bulk delete and bulk update operations.<br />Only ScrollableResultSet can become UpdatableResultSet.<br />
  52. 52. Batch Processing<br />Is a process of combining related queries into single unit, sending them to DB s/w as batch and getting their result as a batch.<br />Instead of sending multiple queries to DB s/w for multiple times, send queries as a batch.<br />Reduces network round trips between java application and DB s/w.<br />Helps the programmer to work with Transactions. <br />
  53. 53. Batch Processing<br />The calls to stmt.addBatch(-) append statements to the original Statement.<br />The call to executeBatch() submits the entire statement with all the appends to the database.<br />The return result of the addBatch method is an array of row counts affected for each statement executed in the batch job.<br />If a problem occurred, a java.sql.BatchUpdateException is thrown.<br />Once select query is executed , it generates ResultSet object. Since ResultSet object cannot be stored in integer array, batch processing cannot include select queries.<br />
  54. 54. Transaction Management<br />Is all about combining set of related operations into a single unit and executing them by applying do everything or nothing principle<br />Transactions are not explicitly opened and closed<br />Instead, the connection has a state called AutoCommit mode<br />if AutoCommit is true, then every statement is automatically committed<br />default case: true<br />
  55. 55. setAutoCommit<br />Connection.setAutoCommit(boolean)<br />if AutoCommit is false, then every statement is added to an ongoing transaction<br />you must explicitly commit or rollback the transaction using Connection.commit() and Connection.rollback()<br />
  56. 56. RowSets<br />We can send only those java objects over the network which are serializable.<br />ResultSet object is not a serializable object, so we cannot send that object over network.<br />To overcome this problem jdbc has given support for RowSet object which are extension to ResultSet object and can be sent over network.<br />All JDBC drivers doesn’t support RowSets.<br />
  57. 57. Performance Tuning For JDBC API<br />
  58. 58. Why Optimize?<br />On average, a web request performs 4 database queries.<br />Experience has shown that database calls are typical performance bottleneck.<br />Bad JDBC can overwhelm the database.<br />
  59. 59. JDBC API<br />SQL: “SELECT * FROM TABLE”<br />java.sql.PreparedStatement<br />java.sql.CallableStatement<br />Cache data on client.<br />MOST VERSATILE<br />MOST OPTIMIZATION<br />
  60. 60. JDBC API<br />SQL STATEMENTS<br />Most flexible<br />Least reliable<br />Must be recompiled in database for each use<br />PREPARED STATEMENT<br />Represents a precompiled SQL statement<br />Can be used to efficiently execute statement multiple times<br />Somewhat flexible –can create new ones as needed<br />
  61. 61. JDBC API<br />CALLABLE STATEMENT<br />Used to execute SQL stored procedures. <br />Same syntax as PreparedStatement.<br />Least flexible.<br />Most optimized DB call.<br />PreparedStatement gives better performance when compared to Statement because it is pre-parsed and pre-compiled by the database once for the first time and then onwards it reuses the parsed and compiled statement.<br />CallableStatement gives better performance when compared to PreparedStatement and Statement when there is a requirement for single request to process multiple complex statements<br />
  62. 62. JDBC API<br />CACHE<br />Keep data within client to reduce the number of round-trips to the database.<br />Every database schema generally has read-only and read-mostly tables. These tables are called as lookup tables.<br />Read-only tables contain static data that never changes in its life time. Read-mostly tables contain semi dynamic data that changes often<br />If an application reads data from these tables for every client request, then it is redundant, unnecessary and expensive.<br /> The solution for this problem is to cache the read-only table data by reading the data from that table once and caching the read-mostly table data by reading and refreshing with time limit<br />
  63. 63. Basic Design Techniques<br />Use Database Connection Pool<br />Don’t useDriverManager.getConnection() often. JDBC connections can take 0.5 to 2 seconds to create.<br />Create Pool of Connections and reuse them.<br />Use multi-threading with Connection Pooling to address network latency<br />Threads can issue queries over separate database connections.<br />OPTIMIZATION WITH RESULTSET OBJECT<br />Set up proper direction for processing the rows<br />Use proper get methods<br />Close ResultSet when finished<br />
  64. 64. Basic Design Techniques<br />Single-batch Transactions<br />Collect set of operations and submit transaction in one statement<br />BEGIN TRANSACTION<br /> UPDATE TABLE1... <br /> INSERT INTO TABLE2…<br /> DELETE TABLE3<br /> COMMIT<br />DB obtains necessary locks on rows and tables, uses and releases them in one step<br />
  65. 65. Basic Design Techniques<br />Smart Queries<br />Make queries as specific as possible<br />Put more logic into SQL statements<br />DB are designed to use SQL efficiently<br />Proper use of SQL can avoid performance problems<br />Smart Query Ex: get employees in ENG dept<br />Instead of: <br /> SELECT * FROM employees;<br /> SELECT * FROM dept;<br /> (and joining on Java application side)<br />Use database join:<br /> SELECT employees.* FROM employees E, dept D WHERE E.DEPTNO = D.DEPTNO AND D.DEPTTYPE = ‘ENG’;<br />
  66. 66. Basic Design Techniques<br />Smart Query Guidelines<br />Use DB for filtering<br />Use Java for business logic<br />DB does filtering very well<br />DB business logic is poor<br />
  67. 67. Connection Pooling<br />There are two types of jdbc connection objects :<br />Direct Connection Object<br />Pooled Connection Object<br />The JDBC Connection object that is created by the programmer manually is called direct connection object.<br />The JDBC Connection object that is collected from JDBC Connection pool is called pooled connection object.<br />JDBC Connection pool is a factory that contains set of readily available JDBC connection objects.<br />
  68. 68. Connection Pooling<br />Using connection pools helps to both alleviate connection management overhead and decrease development tasks for data access.<br />Each time an application attempts to access a backend store (such as a database), it requires resources to create, maintain, and release a connection to that datastore.<br />To mitigate the strain this process can place on overall application resources, the Application Server enables administrators to establish a pool of backend connections that applications can share on an application server<br />
  69. 69. Advantages of Connection Pooling<br />Connection pooling can improve the response time of any application that requires connections, especially Web-based applications.<br />With connection pooling, most user requests do not incur the overhead of creating a new connection because the data source can locate and use an existing connection from the pool of connections<br />Re usability, we can reuse the existing connection already existing<br />It also simplifies the design in terms of managing the connections; we can delegate the connection creation, max number of connections for an application, max idle time for a connection etc. using the some kind of a connection pool manager<br />
  70. 70. C3P0 Connection Pooling<br />c3p0 is an easy-to-use library for making traditional JDBC drivers "enterprise-ready" by augmenting them with functionality defined by the jdbc3 spec and the optional extensions to jdbc2<br />c3p0 provides several useful services:<br />Classes which adapt traditional DriverManager-based JDBC drivers to the new javax.sql.DataSource scheme for acquiring database Connections.<br />Transparent pooling of Connection and PreparedStatements behind DataSources which can "wrap" around traditional drivers or arbitrary unpooledDataSources.<br />
  71. 71. Working with C3P0 Connection Pool<br />Put the file lib/c3p0-0.9.1.2.jar somewhere in your CLASSPATH<br />There are three ways of acquiring c3p0 pool-backed DataSources:<br />directly instantiate and configure a ComboPooledDataSource bean<br />use the DataSources factory class<br />"build your own" pool-backed DataSource by directly instantiating PoolBackedDataSource and setting its ConectionPoolDataSource<br />
  72. 72. Instantiating and Configuring a ComboPooledDataSource<br />the most straightforward way to create a c3p0 pooling DataSource is to instantiate an instance of com.mchange.v2.c3p0.ComboPooledDataSource<br />This is a JavaBean-style class with a public, no-arg constructor<br />Before you use the DataSource, you'll have to be sure to set at least the property jdbcUrl<br />You may also want to set user and password, and if you have not externally preloaded the old-style JDBC driver you'll use you should set the driverClass. <br />
  73. 73. Using the DataSources factory class<br />use the static factory class com.mchange.v2.c3p0.DataSources<br />Can be used to build unpooledDataSources from traditional JDBC drivers<br />Can be used to build pooled DataSources from unpooledDataSources<br />If you use the DataSources factory class, and you want to programmatically override default configuration parameters, you can supply a map of override properties<br />
  74. 74. Java Naming And Directory Interface (JNDI)<br />Java application uses JNDI API to interact with Naming Registry s/w.<br />Every JDBC Connection pool will be represented by Data Source object.<br />To make this data source object publically visible, we register data source object in a special place called naming registry having nick name (jndi name).<br />In order to access a JDBC Connection object of a Connection pool, we need to access the data source object pointing to that connection pool.<br />
  75. 75. Java Naming And Directory Interface (JNDI)<br />Java application needs to perform look up or search operation on naming registry to get the data source object.<br />Use getConnection () method on the data source object to get the connection object from the connection pool.<br />
  76. 76.
  77. 77. An open source DataBase Management System <br />Community Editions free<br />Enterprise Editions free license but a subscription and maintenance fee<br />Suitable situations range from small enterprise to global, enterprise-wide systems <br />Multiple platforms<br />
  78. 78. MySQL Tools<br />The core system includes only a command-line tool<br />‘mysqladmin’<br />GUI tools available separately from MySQL are <br />‘MySQL Administrator’ (a DBA tool) and <br />‘MySQL Query Browser’ <br />
  79. 79. SQLyog is a GUI front-end for MySQL (there are others) - Community and Enterprise Editions<br />Allows Data Definition and Data Manipulation<br />After loading it and before using it you need to ‘Connect’ to the right MySQL instance<br />A tutorial, with a range of activities to get familiar with it, is available at http://www.databasejournal.com/features/mysql/article.php/1558731<br />
  80. 80. SQLyog screen<br />
  81. 81. References<br />For further information see<br />www.mysql.com<br />www.webyog.com/en/ includes forums and FAQs<br />

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