ORA-01000, the maximum-open-cursors error, is an extremely common error in Oracle database development. In the context of Java, it happens when the application. Go to main content. Contents Title and Copyright Information Preface. Audience; Documentation Accessibility. Database Reference - Contents. ![]() Create procedure: alter any procedure: create any procedure: debug any procedure: drop any procedure: execute any procedure. Using PHP with Oracle Database 1. Do not delete this text because it is a placeholder for the generated list of "main" topics when run in a browser> This tutorial shows you how to use PHP with Oracle Database 1. Approximately 2 hours. PHP is a popular web scripting language, and is often used to create database- driven web sites. This tutorial helps you get started with PHP and Oracle Database by showing how to build a web application and by giving techniques for using PHP with Oracle. If you are new to PHP, review the Appendix: PHP Primer to gain an understanding of the PHP language. Before starting this Oracle By Example, please have the following prerequisites completed. Install Oracle Database 1. Start DRCP connection pooling. Create a user named PHPHOL with password of 'welcome'. Install Oracle's sample. Query result cache in oracle 11g. Caching has been a feature of Oracle for as long as most of us can remember. Over the many years and versions, Oracle has.HR schema and make the following changes: create sequence emp_id_seq start with 4. Also to simplify the example we remove this trigger otherwise. PYTHONHOL. JHIST_EMP_ID_ST_DATE_PK constraint. Allow employees to be changed when testing the lab after hours. Install Apache and enable User. Dir module for public_html. Install PHP 5. 3. OCI8 1. 4 extension. In php. ini set: oci. MYPHPAPP. . Extract these files to your $HOME location. This section of the tutorial shows how to use the PHP OCI8 extension directly with Oracle Database. Using the OCI8 extension directly gives programmers maximum control over application performance. To create a connection to Oracle that can be used for the lifetime of the. PHP script, perform the following steps. Review the code in $HOME/public_html/connect. Create connection to Oracle. Connected to Oracle!". Close the Oracle connection. The oci_connect(). In this case, Oracle's Easy Connect connection string syntax is used. It consists of the hostname and the DB service name. The oci_close(). function closes the connection. Any standard connections not explicitly. Open a Web browser and enter the following URL to. Connected to Oracle!" is displayed if the connection succeeds. Review the SQL in $HOME/public_html/usersess. DD- MON- YY HH: MI: SS') logon_time. This is a SQL script file that you run in SQL*Plus. Oracle's command- line SQL scripting tool). This. SQL*Plus script shows the current database sessions, and what time they. Open a terminal window and enter the following commands to run the SQL script. Note that you could also execute the script in SQL Developer. HOME/public_html. The SQL*Plus script lists the current database sessions. The only session shown is for SQL*Plus. The PHP connections from the oci_connect() function has been closed. Edit $HOME/public_html/connect. Reload the connect. Now rerurn usersess. SQL*Plus. cd $HOME/public_html. There should be two connected users. You may see more than two if you reloaded the page several times and Apache allocated different processes to handle the PHP script. By default, persistent connections stay open until the Apache process terminates. Subsequent PHP scripts can reuse the already opened connection, making them run faster. Database Resident Connection Pooling is a new feature of Oracle Database 1. It is useful for short lived scripts such as typically used by web applications. It allows the number of connections to be scaled as web site usage grows. It allows multiple Apache processes on multiple machines to share a small pool of database server processes. Without DRCP, a non- persistent PHP connection must start and terminate a server process, and a persistent PHP connection keeps hold of database resources even when PHP is idle. Below left is diagram of nonpooling. Every script has its own database server proces. Scripts not doing any database work still hold onto a connection until the connection is closed and the server is terminated. Below right is a diagram with DRCP. Scripts can use database servers from a pool of servers and return them when no longer needed. Batch scripts doing long running jobs should generally use non- pooled connections. This section of the tutorial shows. DRCP can be used by new or existing applications without writing or changing. Perform the following steps. Check that php has oci. Open a terminal window and execute the following command: php - r 'echo ini_get("oci. The connection class tells the database server pool. Session information (such as the default. Session information will be discarded if a pooled server is. Review the code in $HOME/public_html/query_pooled. Compare this code to the code in $HOME/public_html/query_nonpooled. The only difference is the ": pooled". Easy Connect connection string in query_pooled. To run the scripts, the Apache Benchmark tool is used. This command repeatedly loads a web page, measuring its performance. From a terminal window, execute the following: ab - c 1. The above command sends Apache 1. Now look at the number of database connections open. Open another terminal window, execute the following: sqlplus phphol/welcome. PHPHOL'; The default DRCP pool MAXSIZE is 4. You see up to 4. 0 connections with PHPHOL username, depending on how many. Apache processes handled the 'ab' requests. You may also need to execute the query while. Oracle manages the DRCP pool, shrinking it after a. Now, you will run the same command except run the. From a terminal window. Now look at the number of database connections open. Open another terminal window, execute the following: sqlplus phphol/welcome. PHPHOL'; Many more rows than previously are returned. The rows. with httpd@localhost. TNS V1- V3)correspond to a running Apache process holding a database. For PHP, Apache runs in a multi- process mode, spawning. PHP script. Depending how. Apache allocated these processes to handle the "ab" requests. V$SESSION. Compare the number of requests completed in each run. You might want to run each script a few times to warm up the caches. Performance of the scripts is roughly similar. For the small works loads used in these two files, the tiny overhead. But the non- pooled script causes every. Apache process to open a separate connection to the database. For larger sites, or where memory is limited, the overall benefits of. DRCP are significant. A common task when developing Web applications is to query. Web browser. There are a number of. Oracle database, but the basics of querying. Parse. the statement for execution. Bind. data values (optional). Execute. the statement. Fetch. the results from the database. To create a simple query, and display the results in an. HTML table, perform the following steps. Review the code in $HOME/public_html/query. Create connection to Oracle. Fetch each row in an associative array. OCI_RETURN_NULLS+OCI_ASSOC)) {. ENT_QUOTES) : '& nbsp').'< /td> '. The oci_parse(). function parses the statement. The oci_execute(). The oci_fetch_array(). The htmlentities(). HTML tags so it displays correctly. From your Web browser, enter the following URL to. The results of the query are displayed in the Web. The OCI_ASSOC parameter fetches the row as an associative arrary of column names and column data. Alternatively, the OCI_NUM parameter can be passed to oci_fetch_array() to fetch the row as a numeric array. Bind variables enable you to re- execute. Bind variables improve code reusability, and can reduce the risk of SQL Injection. To use bind variables in this example, perform the following. Review the code in $HOME/public_html/bind. Fetch the results in an associative array. OCI_RETURN_NULLS+OCI_ASSOC)) {. Create connection to Oracle. Use bind variable to improve resuability. SQL Injection attacks. EIDBV", $myeid). oci_execute($s). Redo query without reparsing SQL statement. Close the Oracle connection. From your Web browser, enter the following URL to. The $myeid. variable is bound to the : eidbv. This allows you to execute the statement again. If you don't see the returned rows, you may have deleted these employees in the web application part of the tutorial. Use SQL*Plus to query the EMPLOYEE_ID column of the EMPLOYEES table, and edit bind. IDs that exist in the table. When you manipulate data in an Oracle Database (insert, update, or delete. When the changed data is committed. This is. a database transaction. By default, when PHP executes a SQL statement it automatically commits. This. can be over- ridden, and the oci_commit(). At the end of a PHP script, any uncommitted. Committing each change individually causes extra load on the server. In general. you want all or none of your data committed. Doing your own transaction. To learn about transaction management in PHP with an Oracle database, perform.
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