| Win32::ODBC - ODBC Extension for Win32 |
Win32::ODBC - ODBC Extension for Win32
To use this module, include the following statement at the top of your script:
use Win32::ODBC;
Next, create a data connection to your DSN:
$Data = new Win32::ODBC("MyDSN");
NOTE: MyDSN can be either the DSN as defined in the ODBC Administrator, or it can be an honest-to-God DSN Connect String.
Example: "DSN=My Database;UID=Brown Cow;PWD=Moo;"
You should check to see if $Data is indeed defined, otherwise there
has been an error.
You can now send SQL queries and retrieve info to your heart's content! See the description of the methods provided by this module below and also the file TEST.PL as referred to in INSTALLATION NOTES to see how it all works.
Finally, MAKE SURE that you close your connection when you are finished:
$Data->Close();
This is a hack of Dan DeMaggio's <dmag@umich.edu> NTXS.C ODBC implementation. I have recoded and restructured most of it including most of the ODBC.PM package, but its very core is still based on Dan's code (thanks Dan!).
The history of this extension is found in the file HISTORY.TXT that comes with the original archive (see INSTALLATION NOTES below).
And what are the benefits of this module?
This package defines a number of constants. You may refer to each of
these constants using the notation ODBC::xxxxx, where xxxxx is
the constant.
Example:
print ODBC::SQL_SQL_COLUMN_NAME, "\n";
For the method documentation that follows, an * following the method parameters indicates that that method is new or has been modified for this version.
DSN, or, if you specify an
already existing ODBC object, then a new ODBC object will be created
but using the ODBC Connection specified by ODBC_OBJECT. (The new
object will be a new hstmt using the hdbc connection in
ODBC_OBJECT.)
DSN is Data Source Name or a proper ODBCDriverConnect string.
You can specify SQL Connect Options that are implemented before the
actual connection to the DSN takes place. These option/values are the
same as specified in GetConnectOption/SetConnectOption (see
below) and are defined in the ODBC API specs.
Returns a handle to the database on success, or undef on failure.
Fetch and Data or DataHash to retrieve the data.
The returned format is:
[Qualifier] [Owner] [Name] [Type]
Returns true on error.
ATTRIBUTE on each of the fields in the list
FIELD_NAMES in the current record set. If FIELD_NAMES is empty,
then all fields are assumed. The attributes are returned as an
associative array.
OPTION takes on one of the following values:
ODBC_ADD_DSN.......Adds a new DSN.
ODBC_MODIFY_DSN....Modifies an existing DSN.
ODBC_REMOVE_DSN....Removes an existing DSN.
ODBC_ADD_SYS_DSN.......Adds a new System DSN.
ODBC_MODIFY_SYS_DSN....Modifies an existing System DSN.
ODBC_REMOVE_SYS_DSN....Removes an existing System DSN.
You must specify the driver DRIVER (which can be retrieved by using
DataSources or Drivers).
ATTRIBUTE1 should be ``DSN=xxx'' where xxx is the name of
the DSN. Other attributes can be any DSN attribute such as:
"UID=Cow"
"PWD=Moo"
"Description=My little bitty Data Source Name"
Returns true on success, false on failure.
NOTE 1: If you use ODBC_ADD_DSN, then you must include at least
``DSN=xxx'' and the location of the database.
Example: For MS Access databases, you must specify the DatabaseQualifier:
"DBQ=c:\\...\\MyDatabase.mdb"
NOTE 2: If you use ODBC_MODIFY_DSN, then you need only specify
the ``DNS=xxx'' attribute. Any other attribute you include will be
changed to what you specify.
NOTE 3: If you use ODBC_REMOVE_DSN, then you need only specify
the ``DSN=xxx'' attribute.
FIELD_NAME or the current row
(if nothing is specified).
FIELD1, FIELD2, ... or the entire row (if
nothing is specified) as an associative array consisting of:
{Field Name} => Field Data
$ArrayName{'DSN'}=Driver
where DSN is the Data Source Name and ODBC Driver used.
Returns the debugging value (1 or 0).
$ArrayName{'DRIVER'}=Attrib1;Attrib2;Attrib3;...
where DRIVER is the ODBC Driver Name and AttribX are the driver-defined attributes.
SetStmtCloseType, but the
ODBC object does not lose the StmtCloseType setting. CLOSE_TYPE
can be any valid SmtpCloseType and will perform a close on the stmt
using the specified close type.
Returns true on success, false on failure.
If called in a scalar context, then a 3-element array is returned:
( ERROR_NUMBER, ERROR_TEXT, CONNECTION_NUMBER )
If called in a string context, then a string is returned:
"[ERROR_NUMBER] [CONNECTION_NUMBER] [ERROR_TEXT]"
If debugging is on then two more variables are returned:
( ..., FUNCTION, LEVEL )
where FUNCTION is the name of the function in which the error
occurred, and LEVEL represents extra information about the error
(usually the location of the error).
ROW and/or TYPE
are specified, the call is made using SQLExtendedFetch instead of
SQLFetch.
NOTE 1: If you are unaware of SQLExtendedFetch and its
implications, stay with just regular FetchRow with no parameters.
NOTE 2: The ODBC API explicitly warns against mixing calls to
SQLFetch and SQLExtendedFetch; use one or the other but not
both.
If ROW is specified, it moves the keyset RELATIVE ROW number
of rows.
If ROW is specified and TYPE is not, then the type used is
RELATIVE.
Returns true when another record is available to read, and false when there are no more records.
OPTION. Refer to
ODBC documentation for more information on the options and values.
Returns a string or scalar depending upon the option specified.
Returns an array of field data where the first element is either false (if successful) and true (if not successful).
If no DSN is specified then the current connection is used.
The returned associative array consists of:
keys=DSN keyword; values=Keyword value. $Data{$Keyword}=Value
FUNCTION must be in the form of an ODBC API constant like
SQL_API_SQLTRANSACT.
The returned array will contain the results like:
$Results{SQL_API_SQLTRANSACT}=Value
Example:
$Results = $O->GetFunctions(
$O->SQL_API_SQLTRANSACT,
SQL_API_SQLSETCONNECTOPTION
);
$ConnectOption = $Results{SQL_API_SQLSETCONNECTOPTION};
$Transact = $Results{SQL_API_SQLTRANSACT};
SetMaxBufSize.
SetStmtCloseType for details.
By default, the connection of the current object will be used. If
CONNECTION is a valid connection number, then it will be used.
OPTION. Refer
to ODBC documentation for more information on the options and values.
Returns a string or scalar depending upon the option specified.
Example:
"SELECT * FROM [foo] SELECT * FROM [bar]"
NOTE: Not all drivers support this.
Returns 1 if there is more data, undef otherwise.
NOTE 1: This function is not supported by all ODBC drivers! Some drivers do support this but not for all statements (e.g., it is supported for UPDATE, INSERT and DELETE commands but not for the SELECT command).
NOTE 2: Many data sources cannot return the number of rows in a result set before fetching them; for maximum interoperability, applications should not rely on this behavior.
Returns the number of affected rows, or -1 if not supported by the driver in the current context.
No return value.
Returns true on success, false otherwise.
Returns true on success, false otherwise.
ROW within the current keyset (not
the current data/result set).
Returns true on success, false otherwise.
The amount of memory that is allocated to retrieve the field data of a record is dynamic and changes when it need to be larger. I found that a memo field in an MS Access database ended up requesting 4 Gig of space. This was a bit much so there is an imposed limit (2,147,483,647 bytes) that can be allocated for data retrieval.
Since it is possible that someone has a database with field data greater than 10,240, you can use this function to increase the limit up to a ceiling of 2,147,483,647 (recompile if you need more).
Returns the max number of bytes.
ODBCFreeStmt(hstmt, TYPE). By default, the connection of
the current object will be used. If CONNECTION is a valid
connection number, then it will be used.
TYPE may be one of:
SQL_CLOSE
SQL_DROP
SQL_UNBIND
SQL_RESET_PARAMS
Returns a string indicating the newly set type.
OPTION. Refer to
ODBC documentation for more information on the options and values.
Returns true on success, false otherwise.
No return value.
SQL_STRING on the current connection.
Returns ? on success, or an error number on failure.
Returns an array of table names.
TYPE may be one of:
SQL_COMMIT
SQL_ROLLBACK
NOTE: This only works with ODBC drivers that support transactions. Your driver supports it if true is returned from:
$O->GetFunctions($O->SQL_API_SQLTRANSACT)[1]
(See GetFunctions for more details.)
Returns true on success, false otherwise.
PACKAGES is empty, then
all version numbers are returned.
What known problems does this thing have?
SQLConnection. I don't think that this is a problem with the code,
but more like a problem with ODBC. This happens because some ODBC
drivers need to write a temporary file. I noticed this using the MS
Jet Engine (Access Driver).
This module has been neither optimized for speed nor optimized for
memory consumption.
If you wish to use this module with a build of Perl other than ActivePerl, you may wish to fetch the original source distribution for this module at:
ftp://ftp.roth.net:/pub/ntperl/ODBC/970208/Bin/Win32_ODBC_Build_CORE.zip
or one of the other archives at that same location. See the included README for hints on installing this module manually, what to do if you get a parse exception, and a pointer to a test script for this module.
Find a FAQ for Win32::ODBC at:
http://www.roth.net/odbc/odbcfaq.htm
Dave Roth <rothd@roth.net>
Based on original code by Dan DeMaggio <dmag@umich.edu>
I do not guarantee ANYTHING with this package. If you use it you are doing so AT YOUR OWN RISK! I may or may not support this depending on my time schedule.
Last Modified 1999.09.25.
Copyright (c) 1996-1998 Dave Roth. All rights reserved.
Courtesy of Roth Consulting: http://www.roth.net/consult/
Use under GNU General Public License. Details can be found at: http://www.gnu.org/copyleft/gpl.html
| Win32::ODBC - ODBC Extension for Win32 |