Database 20/2/12 Connection

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3 Client PC Request Data stored on DB Db Web Server – Corvus 3 Data retrieved from Db and sent to browser window

 This ability to access multiple types of data stores with a relative simple and flat object model, make ADO the simplest method yet devised for retrieving data ◦ ADO works with ODBC compliant sources 4

 The Connection Object is used to hold information about the data store you want to access  Because it is an Object it has properties and methods  Some of these will be needed when creating you PHP application 5

 Before you can retrieve any data from a database, you have to create and initalise a connection to that database  ADODB contains all the ADO objects that you will need to use  In order to use any of the Object from the ADO Object Model you will need to create them  PHP uses the following syntax for creating an Instance of an object $conn = new COM ("ADODB.Connection") or die("Cannot start ADO"); Note: we store the connection in a variable ($conn) for later use in the script. The "die" part will be executed if the connection fails. 6

 Connection String ‘tells’ your connection what database you wish to connect to.  If you have a system DSN set up all you need do is supply this when setting the connection String.  This is the simplest form of string that can be used.  The connection can also be used for a DSN-less connection. 7

$connStr = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=c:\Inetpub\wwwroot\MBSEBus\CHeav in\Databases\cus.accdb"; Note: WWWRoot is a hidden folder (by default) and can't be displayed in directory listing 8

 Connection strings are string variables which contain database connection information and then passed to ADO(ActiveX Data Objects) which will interpret them and act accordingly  They need to be in a comprehensible for ADO format  If you're connecting to an MS Access database, you need the DRIVER, and the DBQ, and some other optional information 9

 When the you have created an instance of the connection object and you have created the assigned a connection string you then need to explicitly open the connection to the database.  To open a connection: $conn->open($connStr);  If the Open method executes you have a working connection to the database 10

 As with any Object you need to free the memory associated with it when you are finished.  However, before you do that, you need to close the connection $conn->Close(); 11

 If you wanted to close the connection but connect to a different data source, you can use the same instance of the connection object.  Simply close the connection first, the set the connection information appropriately and, and reopen it. 12

 Setting up the recordset $rS = $conn->execute("SELECT * FROM test"); 13

After connecting to a database. You may want to do all or some of the following: ◦ Read Data ◦ Write Data ◦ Delete Data 14

◦ Recordset is simply a set of records. ◦ The Recordset may be used to contain  a subset of all the records in a table  All the records in a table.  A specifically chosen set of records  Using a specific SQL statement.  You will need to create an instance of the recordset object before you can use it 15

$rS = $conn->execute("SELECT * FROM test"); $f1 = $rS->Fields(0); $f2 = $rS->Fields(1); while (!$rS->EOF) { print $f1->value." ".$f2->value." \n"; $rS->MoveNext(); } $rS->Close(); 16

Untitled 1 <?php //create an instance of the ADO connection object $conn = new COM ("ADODB.Connection") or die("Cannot start ADO"); //define connection string, specify database driver $connStr = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=c:\Inetpub\wwwroot\MBSEBus\CHeavin\Databases\cus.accdb"; //Open the connection to the database $conn->open($connStr); echo "Connection Open "; //recordset code $rS = $conn->execute("SELECT * FROM test"); $f1 = $rS->Fields(0); $f2 = $rS->Fields(1); while (!$rS->EOF) { print $f1->value." ".$f2->value." \n"; $rS->MoveNext(); } $rS->Close(); $conn->Close(); ?> 17 Select Records

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Example: $sql="UPDATE test SET name='Mary' WHERE name='Ciaran'"; 19

Untitled 1 <?php //create an instance of the ADO connection object $conn = new COM ("ADODB.Connection") or die("Cannot start ADO"); //define connection string, specify database driver $connStr = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=c:\Inetpub\wwwroot\mbsebus\CHeavin\Databases\cus.accdb"; //Open the connection to the database $conn->open($connStr); echo "Connection Open "; $sql="UPDATE test SET name='Ciara' WHERE name='harry'"; $rS = $conn->execute($sql); echo "Record Updated "; $conn->Close(); ?> 20

$sql="DELETE * FROM test WHERE name='barry'"; 21

Untitled 1 <?php //create an instance of the ADO connection object $conn = new COM ("ADODB.Connection") or die("Cannot start ADO"); //define connection string, specify database driver $connStr = "PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=c:\Inetpub\wwwroot\mbsebus\CHeavin\Databases\cus.accdb"; //Open the connection to the database $conn->open($connStr); $sql="DELETE * FROM test WHERE name='Ciara'"; echo "Connection Open "; $rS = $conn->execute($sql); print "Record Deleted"; $conn->Close(); ?> 22

$sql="INSERT INTO test (name,age) VALUES ('".$name1."','".$age1."' );"; //Set SQL query 23

Untitled 1 <?php //create an instance of the ADO connection object $conn = new COM ("ADODB.Connection") or die("Cannot start ADO"); //define connection string, specify database driver $connStr="PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=c:\Inetpub\wwwroot\mbsebus\CHeavin\Databases\cus.accdb"; //Open the connection to the database $conn->open($connStr); echo "Connection Open "; $name1="barack obama"; $age1="32"; $sql="INSERT INTO test (name,age) VALUES ('".$name1."','".$age1."' );"; //Set SQL query $conn->Execute($sql); //Execute SQL query print "Record Inserted"; $conn->Close(); //Close database connection ?> 24

Join Name: Age: 25

Untitled 1 New User Name: Age: <?php //create an instance of the ADO connection object $conn = new COM ("ADODB.Connection") or die("Cannot start ADO"); //define connection string, specify database driver $connStr="PROVIDER=Microsoft.ACE.OLEDB.12.0;Data Source=c:\Inetpub\wwwroot\mbsebus\CHeavin\Databases\cus.accdb"; //Open the connection to the database $conn->open($connStr); $name=$_POST['cust_name']; $age=$_POST['cust_age']; $sql="INSERT INTO test (name,age) VALUES ('".$name."','".$age."' );"; //Set SQL query $conn->Execute($sql); //Execute SQL query $conn->Close(); //Close database connection ?> 26