php odbc连接informix,该怎么解决

php odbc连接informix
怎样设置odbc?php代码如何写,哪位高手能给出详细的代码。

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php没用过。
建立dsn。用odbc_connect连接,
抄来的例子,和数据库无关。
Create an ODBC Connection
With an ODBC connection, you can connect to any database, on any computer in your network, as long as an ODBC connection is available.

Here is how to create an ODBC connection to a MS Access Database: 

1.Open the Administrative Tools icon in your Control Panel.
2.Double-click on the Data Sources (ODBC) icon inside. 
3.Choose the System DSN tab. 
4.Click on Add in the System DSN tab. 
5.Select the Microsoft Access Driver. Click Finish. 
6.In the next screen, click Select to locate the database. 
7.Give the database a Data Source Name (DSN). 
8.Click OK.
Note that this configuration has to be done on the computer where your web site is located. If you are running Internet Information Server (IIS) on your own computer, the instructions above will work, but if your web site is located on a remote server, you have to have physical access to that server, or ask your web host to to set up a DSN for you to use.


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Connecting to an ODBC
The odbc_connect() function is used to connect to an ODBC data source. The function takes four parameters: the data source name, username, password, and an optional cursor type.

The odbc_exec() function is used to execute an SQL statement.

Example
The following example creates a connection to a DSN called northwind, with no username and no password. It then creates an SQL and executes it:

$conn=odbc_connect('northwind','','');
$sql="SELECT * FROM customers";
$rs=odbc_exec($conn,$sql); 

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