XCIV. ODBC Functions (Unified)

简介

In addition to normal ODBC support, the Unified ODBC functions in PHP allow you to access several databases that have borrowed the semantics of the ODBC API to implement their own API. Instead of maintaining multiple database drivers that were all nearly identical, these drivers have been unified into a single set of ODBC functions.

The following databases are supported by the Unified ODBC functions: Adabas D, IBM DB2, iODBC, Solid, and Sybase SQL Anywhere.

注: There is no ODBC involved when connecting to the above databases. The functions that you use to speak natively to them just happen to share the same names and syntax as the ODBC functions. The exception to this is iODBC. Building PHP with iODBC support enables you to use any ODBC-compliant drivers with your PHP applications. iODBC is maintained by OpenLink Software. More information on iODBC, as well as a HOWTO, is available at www.iodbc.org.

需求

To access any of the supported databases you need to have the required libraries installed.

安装

--with-adabas[=DIR]

Include Adabas D support. DIR is the Adabas base install directory, defaults to /usr/local.

--with-sapdb[=DIR]

Include SAP DB support. DIR is SAP DB base install directory, defaults to /usr/local.

--with-solid[=DIR]

Include Solid support. DIR is the Solid base install directory, defaults to /usr/local/solid.

--with-ibm-db2[=DIR]

Include IBM DB2 support. DIR is the DB2 base install directory, defaults to /home/db2inst1/sqllib.

--with-empress[=DIR]

Include Empress support. DIR is the Empress base install directory, defaults to $EMPRESSPATH. From PHP 4, this option only supports Empress Version 8.60 and above.

--with-empress-bcs[=DIR]

Include Empress Local Access support. DIR is the Empress base install directory, defaults to $EMPRESSPATH. From PHP 4, this option only supports Empress Version 8.60 and above.

--with-birdstep[=DIR]

Include Birdstep support. DIR is the Birdstep base install directory, defaults to /usr/local/birdstep.

--with-custom-odbc[=DIR]

Include a user defined ODBC support. The DIR is ODBC install base directory, which defaults to /usr/local. Make sure to define CUSTOM_ODBC_LIBS and have some odbc.h in your include dirs. E.g., you should define following for Sybase SQL Anywhere 5.5.00 on QNX, prior to run configure script: CPPFLAGS="-DODBC_QNX -DSQLANY_BUG" LDFLAGS=-lunix CUSTOM_ODBC_LIBS="-ldblib -lodbc".

--with-iodbc[=DIR]

Include iODBC support. DIR is the iODBC base install directory, defaults to /usr/local.

--with-esoob[=DIR]

Include Easysoft OOB support. DIR is the OOB base install directory, defaults to /usr/local/easysoft/oob/client.

--with-unixODBC[=DIR]

Include unixODBC support. DIR is the unixODBC base install directory, defaults to /usr/local.

--with-openlink[=DIR]

Include OpenLink ODBC support. DIR is the OpenLink base install directory, defaults to /usr/local. This is the same as iODBC.

--with-dbmaker[=DIR]

Include DBMaker support. DIR is the DBMaker base install directory, defaults to where the latest version of DBMaker is installed (such as /home/dbmaker/3.6).

To disable unified ODBC support in PHP 3 add --disable-unified-odbc to your configure line. Only applicable if iODBC, Adabas, Solid, Velocis or a custom ODBC interface is enabled.

PHP 的 Windows 版本已经内置该扩展模块的支持。无需加载任何附加扩展库即可使用这些函数。

运行时配置

这些函数的行为受 php.ini 的影响。

表格 1. Unified ODBC Configuration Options

NameDefaultChangeableChangelog
odbc.default_db *NULLPHP_INI_ALL 
odbc.default_user *NULLPHP_INI_ALL 
odbc.default_pw *NULLPHP_INI_ALL 
odbc.allow_persistent"1"PHP_INI_SYSTEM 
odbc.check_persistent"1"PHP_INI_SYSTEM 
odbc.max_persistent"-1"PHP_INI_SYSTEM 
odbc.max_links"-1"PHP_INI_SYSTEM 
odbc.defaultlrl"4096"PHP_INI_ALL 
odbc.defaultbinmode"1"PHP_INI_ALL 

注: Entries marked with * are not implemented yet.

有关 PHP_INI_* 常量进一步的细节与定义参见附录 G

以下是配置选项的简要解释。

odbc.default_db string

ODBC data source to use if none is specified in odbc_connect() or odbc_pconnect().

odbc.default_user string

User name to use if none is specified in odbc_connect() or odbc_pconnect().

odbc.default_pw string

Password to use if none is specified in odbc_connect() or odbc_pconnect().

odbc.allow_persistent boolean

Whether to allow persistent ODBC connections.

odbc.check_persistent boolean

Check that a connection is still valid before reuse.

odbc.max_persistent integer

The maximum number of persistent ODBC connections per process.

odbc.max_links integer

The maximum number of ODBC connections per process, including persistent connections.

odbc.defaultlrl integer

Handling of LONG fields. Specifies the number of bytes returned to variables.

当使用 integer 类型时,其值以字节为度量单位。还可以用简化符号,说明见此 FAQ

odbc.defaultbinmode integer

Handling of binary data.

资源类型

本扩展模块未定义任何资源类型。

预定义常量

以下常量由本扩展模块定义,因此只有在本扩展模块被编译到 PHP 中,或者在运行时被动态加载后才有效。

ODBC_TYPE (integer)

ODBC_BINMODE_PASSTHRU (integer)

ODBC_BINMODE_RETURN (integer)

ODBC_BINMODE_CONVERT (integer)

SQL_ODBC_CURSORS (integer)

SQL_CUR_USE_DRIVER (integer)

SQL_CUR_USE_IF_NEEDED (integer)

SQL_CUR_USE_ODBC (integer)

SQL_CONCURRENCY (integer)

SQL_CONCUR_READ_ONLY (integer)

SQL_CONCUR_LOCK (integer)

SQL_CONCUR_ROWVER (integer)

SQL_CONCUR_VALUES (integer)

SQL_CURSOR_TYPE (integer)

SQL_CURSOR_FORWARD_ONLY (integer)

SQL_CURSOR_KEYSET_DRIVEN (integer)

SQL_CURSOR_DYNAMIC (integer)

SQL_CURSOR_STATIC (integer)

SQL_KEYSET_SIZE (integer)

SQL_CHAR (integer)

SQL_VARCHAR (integer)

SQL_LONGVARCHAR (integer)

SQL_DECIMAL (integer)

SQL_NUMERIC (integer)

SQL_BIT (integer)

SQL_TINYINT (integer)

SQL_SMALLINT (integer)

SQL_INTEGER (integer)

SQL_BIGINT (integer)

SQL_REAL (integer)

SQL_FLOAT (integer)

SQL_DOUBLE (integer)

SQL_BINARY (integer)

SQL_VARBINARY (integer)

SQL_LONGVARBINARY (integer)

SQL_DATE (integer)

SQL_TIME (integer)

SQL_TIMESTAMP (integer)

SQL_TYPE_DATE (integer)

SQL_TYPE_TIME (integer)

SQL_TYPE_TIMESTAMP (integer)

SQL_BEST_ROWID (integer)

SQL_ROWVER (integer)

SQL_SCOPE_CURROW (integer)

SQL_SCOPE_TRANSACTION (integer)

SQL_SCOPE_SESSION (integer)

SQL_NO_NULLS (integer)

SQL_NULLABLE (integer)

SQL_INDEX_UNIQUE (integer)

SQL_INDEX_ALL (integer)

SQL_ENSURE (integer)

SQL_QUICK (integer)

目录
odbc_autocommit -- Toggle autocommit behaviour
odbc_binmode -- Handling of binary column data
odbc_close_all -- Close all ODBC connections
odbc_close -- Close an ODBC connection
odbc_columnprivileges --  Returns a result identifier that can be used to fetch a list of columns and associated privileges
odbc_columns --  Lists the column names in specified tables
odbc_commit -- Commit an ODBC transaction
odbc_connect -- Connect to a datasource
odbc_cursor -- Get cursorname
odbc_data_source -- Returns information about a current connection
odbc_do -- Synonym for odbc_exec()
odbc_error -- Get the last error code
odbc_errormsg -- Get the last error message
odbc_exec -- Prepare and execute a SQL statement
odbc_execute -- Execute a prepared statement
odbc_fetch_array -- Fetch a result row as an associative array
odbc_fetch_into -- Fetch one result row into array
odbc_fetch_object -- Fetch a result row as an object
odbc_fetch_row -- Fetch a row
odbc_field_len -- Get the length (precision) of a field
odbc_field_name -- Get the columnname
odbc_field_num -- Return column number
odbc_field_precision -- Synonym for odbc_field_len()
odbc_field_scale -- Get the scale of a field
odbc_field_type -- Datatype of a field
odbc_foreignkeys --  Returns a list of foreign keys in the specified table or a list of foreign keys in other tables that refer to the primary key in the specified table
odbc_free_result -- Free resources associated with a result
odbc_gettypeinfo --  Returns a result identifier containing information about data types supported by the data source
odbc_longreadlen -- Handling of LONG columns
odbc_next_result --  Checks if multiple results are available
odbc_num_fields -- Number of columns in a result
odbc_num_rows -- Number of rows in a result
odbc_pconnect -- Open a persistent database connection
odbc_prepare -- Prepares a statement for execution
odbc_primarykeys --  Returns a result identifier that can be used to fetch the column names that comprise the primary key for a table
odbc_procedurecolumns --  Retrieve information about parameters to procedures
odbc_procedures --  Get the list of procedures stored in a specific data source
odbc_result_all -- Print result as HTML table
odbc_result -- Get result data
odbc_rollback -- Rollback a transaction
odbc_setoption --  Adjust ODBC settings
odbc_specialcolumns --  Returns either the optimal set of columns that uniquely identifies a row in the table or columns that are automatically updated when any value in the row is updated by a transaction
odbc_statistics -- Retrieve statistics about a table
odbc_tableprivileges --  Lists tables and the privileges associated with each table
odbc_tables --  Get the list of table names stored in a specific data source

add a note add a note User Contributed Notes
11-Oct-2006 10:28
I had big performance problems retrieving data form MS SQL Server with odbc only when the query was unsing a join.

I found out, that I had to connect with the cursor-type "SQL_CUR_USE_ODBC" and everything was ok:

$conn = odbc_connect("ShopLive", 'shop', 'xxx', SQL_CUR_USE_ODBC);
sven at ajaxtechforums dot com
28-Feb-2006 07:07
I found this to be a perfect alternative to the MaxDB special drivers of version 7.5.00. Just weren't that easy to install on *nix. Windows seems fine. Anyway The ODBC is a perfect alternative for connecting the SAPDB/MaxDB towards PHP.

Installation guide for the odbc alternative (instead of the MAXDB-php driver) can be found here:

http://maxdb.yapabout.com/viewtopic.php?t=21
xangelusx at hotmail dot com
11-Nov-2005 11:45
If you receive an error stating "Connection is busy with results for another hstmt, SQL state S1000 in SQLExecDirect" try opening your odbc connection using the SQL_CURSOR_FORWARD_ONLY option

<?php
$db_link
= odbc_connect($dsn, $username, $password, SQL_CURSOR_FORWARD_ONLY)
   or die(
'Error connecting to server. Server says: '.htmlspecialchars(odbc_errormsg()));
?>
Quickdraw
06-May-2005 02:06
In response to Holger's comment about using @@identity:

Be carefull. If the table you're inserting into has a trigger that also inserts into another table that has an identity column you'll get the key of that other table! use scope_identity() instead of @@identity
05-May-2005 11:14
I searched for the solution of why odbc connection of a network remote drive under Windows + Apache 2.0.X, cannot give the query, but seems no one provides the solution.

In fact, it is very simple.
Go to Control Panal -> Services;
Find and double click "Apache2";
In the page of "Log On", choose Log on as "This account" and give an account in the web server system which have the right to control the network remote drive;
Finally, restart Apache, and that's it.
philip
08-Mar-2005 07:13
A good tutorial for odbc + php can be found here (written by the good folks at IBM Developer Works):
* http://tinyurl.com/3w8s4
denials at gmail dot com
24-Jan-2005 07:05
Ever wonder why you're experiencing really slow data retrieval times using IBM DB2 Universal Database for Linux, UNIX, and Windows? The default cursor type used by Unified ODBC is not supported by DB2, so it gets downgraded to a forward-only cursor -- and that negotiation occurs with every row fetch.

One way to force your PHP applications to use forward-only cursors is to modify your DB2 client configuration with a handy CLI patch2 setting value of 6:

$ db2 UPDATE CLI CONFIGURATION FOR SECTION dbname USING patch2 6

You have to update this client setting on the same machine on which you are running the PHP application. This works on Windows operating systems as well as on Linux & UNIX operating systems.

I ran a few basic benchmarks (fetch 10,000 rows consisting of 3 INTEGER columns from a remote database server) and concluded that this setting can make a major difference to your application speed:

Without CLI patch2 setting: ~22 seconds
With CLI patch2 setting: ~ 1.75 seconds

Note that the drawback of using this patch setting (or any other method of using forward-only cursors) makes odbc_num_rows() always return "-1" for the number of rows affected by a SELECT statement.
pascals at NOSPAM dot pobox dot com
28-Feb-2004 07:15
If the bundled ODBC library stumbles on some field formats (like some REAL from Pervasive.SQL), have a look at http://odbtp.sourceforge.net/.

After many headaches, I have adoped odbtp: it's a very solid library and best of all it's not tied to a particular OS.
vbwebprofi at gmx dot de
04-Nov-2003 08:31
On my search for a function to retriew the NewID of an inserted row wich has an autoincrement I found this solution like the mysql_insert_id for an ODBC connection to MS-Access :

<?
// make your connection below
$Connection = odbc_connect(...);
$Result = odbc_exec($Connection, "select @@identity");
$NewID = odbc_result($Result, 1);
odbc_free_result($Result);

// make here all what you want with the NewID

odbc_close($Connection);
?>

In my mind this should also work with MS-SQL-Server and with Sybase - via ODBC and direct (mssql_.../sybase_...).

HTH ...

Regards

Holger
b dot parish at no_spam dot linst dot ac dot uk
14-Aug-2002 11:46
Accessing a Microsoft SQL Server database from PHP running under Linux:

http://www.phpbuilder.com/columns/alberto20000919.php3?page=4
dan dot polansky at seznam dot cz
03-Mar-2001 02:37
First I just repeat that examples are here:

http://php.weblogs.com/odbc

Second: Despite confusing remarks above, using unified ODBC functions you can really connect to any database for which you create DSN (Data Source Name). That is: using unified ODBC functions you can connect to _any_ database for which you have ODBC driver. Drivers exists or example Interbase, VisualFoxPro, DBase III,IV,V etc, many drivers are part of Win98 installation, other can be obtained from companies like EasySoft and Merant. ODBC is one of the most flexible ways for connecting to databases. This is because ODBC driver exist for almost every database there is. The question is, whether the driver is free. At least there are many 30 days trial versions of drivers.