Win32::ODBC - Object

Contents

Part I

• Module Description
• Business Stuff
  • Copyright Notice
  • Disclaimer
  • GNU General Public License
  • Larry Wall's "Artistic License"
• Version History
  • Author List
• Features/Limits
• Installation Instructions
• Bug Reports
• Latest Versions
• For More Information on Perl

Part II

• Creating an ODBC Object
• Object Methods
  • Catalog()
  • Connection()
  • Close()
  • Data()
  • DataHash()
  • DataSources()
  • Drivers()
  • DumpError()
  • DumpData()
  • Error()
  • FetchRow()
  • FieldNames()
  • GetConnections()
  • GetDSN()
  • GetStmtCloseType()
  • GetMaxBufSize()
  • MoreResults()
  • new()
  • RowCount()
  • Run()
  • SetMaxBufSize()
  • SetStmtCloseType()
  • Shutdown()
  • Sql()
  • TableList()
• Examples

Creating an ODBC Object

	use Win32::ODBC;

	$Data = new Win32::ODBC("MyDSN");

Make sure that you close your connection when you are finished:

	$Data->Close();

Object Methods

General Note

	use Win32::ODBC;

	$db = new Win32::ODBC("MyDSN");

Also, in an effort to keep the examples short, no error checking is done on return values for any calls other than the one being exemplified. You should always check for error conditions in production code.

WARNING: The example code has not yet been tested. This will be fixed ASAP, but be forwarned!

Methods

Catalog qualifier, owner, name, type

Retrieves the catalog from the current ODBC object. Returns a four-element array (Qualifier, Owner, Name, Type). Note:All fieldnames are uppercase!

Example:
($qualifier, $owner, $name, $type) = $db->Catalog("", "", "%", "'TABLE'");

Connection

Returns the object's ODBC connection number.

Example:
$cnum = $db->Connection;

Close

Closes the ODBC connection for this object. It always returns undef.

Example:												  
$db->Close();

Data

Data list

Retrieve data from previous fetch for a list of field names. In a scalar context it returns all of the field values concatenated together. In an array context, it returns an array of the values, in the order in which they were specified. If no field names are given, all fields are returned in an unspecified order.

Example:
$db->Sql("SELECT f1, f2, f3 FROM foo");
$db->FetchRow();
($f1, $f2) = $db->Data("f1", "f2");

or

$db->Sql("SELECT * FROM foo");
$db->FetchRow();
@values = $db->Data;

See also: DataHash

DataHash

DataHash list

Retrieve data from previous fetch for a list of field names. Returns a hash where the field name is the key. If no field names are given, all fields are returned.

Example:
$db->Sql("SELECT f1, f2, f3 FROM foo");
$db->FetchRow();
%hash = $db->DataHash("f1", "f2");
print $hash{f1};

or

$db->Sql("SELECT * FROM foo");
$db->FetchRow();
%hash = $db->DataHash;
foreach $key (sort(keys %hash)) {
	print $key, '=', $hash{$key}, "\n";
}

See also: Data

DataSources

Returns an associative array of Data Sources and ODBC remarks in the form of:

$ArrayName{'DSN'} = Remark

where DSN is the Data Source Name and Remark is, well, the remark.

Example:
%rem = $db->DataSources;
print LOG qq(Current DSN's Remark: "), %rem{$db->GetDSN}, qq("\n);

Drivers

Returns an associative array of Drivers and their attributes in the form of:

$ArrayName{'DRIVER'} = Attrib1;Attrib2;Attrib3;...

where DRIVER is the ODBC Driver Name and AttribX are the driver-defined attributes.

Example:
%attrib = $db->Drivers;
print LOG qq($driver: $attrib{$driver}\n) foreach $driver (keys %attrib);

DumpError

Dump to the screen details about the last error condition. This includes error number, error text and the ODBC connection number that caused the error (if there is one). This is used primarily for debugging.

Example:
$db = new Win32::ODBC("My DSN");
if (undef $db){
    Win32::ODBC::DumpError();
}
if ($db->Sql("Select * FROM foo")){
    $db->DumpError;
}

DumpData

Dump to the screen all field names and the data in all rows of the current dataset. This is used primarily for debugging.

Example:
$db->Sql("Select * FROM foo");
$db->DumpData;

Error

Returns the last recorded error in the form of an array or string (depending upon the context) containing the error number, error text and the ODBC connection that caused the error (if there is one).

Example:
die $db->Error(), qq(\n);

($ErrNum, $ErrText, $ErrConn) = $db->Error();

FetchRow

Fetches the next row of data from the previous specified SQL statement. You would then call Data or DataHash to actually retrieve the individual elements of data. Returns undef if there's an error, TRUE otherwise.

Example:
$db->Sql("SELECT * FROM foo");
$db->FetchRow() || die qq(Fetch error: ), $db->Error(), qq(\n);
$f1 = $db->Data("f1");

See also: Sql, Data, DataHash

FieldNames

Returns a list of field names extracted from the current dataset. This is used mostly for testing/debugging. FieldNames returns the data in an array, with no guarantee of the order of the names.

Example:
$db->Sql("SELECT * FROM foo");
$db->FetchRow();
foreach $fd ($db->FieldNames()) print qq($fd: "), $db->Data($fd), qq("\n);

GetConnections

Returns an array of connection numbers for all objects.

Example:
@cnums = $db->GetConnections;

GetDSN

GetDSN conn

Returns the DSN (Data Source Name) or the ODBCDriverConnect string for the connection conn, or the current connection if not specified.

Example:
print LOG qq(Current connection: "), $db->GetDSN, qq("\n);

GetMaxBufSize

Returns the current maximum single field data size, in bytes.

Example:
$max = $db->GetMaxBufSize;
$db->SetMaxBufSize($needed) if ($max < $needed);

See also: SetMaxBufSize

GetStmtCloseType

Returns the current ODBC close type setting. This is used mainly for debugging. Type will be one of: SQL_CLOSE, SQL_DROP, SQL_UNBIND, or SQL_RESET_PARAMS. See SetStmtCloseType for more info on what each of the types mean, and how they are used.

Example:
$oldct = $db->GetStmtCloseType;
$db->SetStmtCloseType(SQL_DROP);
...
$db->SetStmtCloseType($oldct);

See also: SetStmtCloseType

MoreResults

Sees if more result sets are present and initializes for fetching rows from next result set. You would then call FetchRow to actually fetch the next row of the next result set. Returns undef if there's an error, TRUE otherwise.

Example:
$db->Sql("SELECT * FROM foo\n  SELECT * FROM bar");
$db->FetchRow() || die qq(Fetch error: ), $db->Error(), qq(\n);
$f1 = $db->Data("f1");
$db->MoreResults() || die qq(Error checking for more result sets: ), $db->Error(), qq(\n);
$db->FetchRow() || die qq(Fetch error: ), $db->Error(), qq(\n);
$f1 = $db->Data("f1");

See also: Sql, Data

new Win32::ODBC(DSN)

new Win32::ODBC(ODBCDriverConnect)

Creates a new ODBC object, given a DSN (Data Source Name) or a properly formatted ODBCDriverConnect string. Returns the created ODBC object or undef if there is an error.

Example:
$DSN = "MyDSN";
$db = new Win32::ODBC($DSN);
die qq(Cannot open new ODBC\n) if ! $db;

or

$db = new Win32::ODBC("dsn=FOO;UID=BAR;PWD=FUBAR");
die qq(Cannot open new ODBC\n) if ! $db;

RowCount

Returns the number of rows that were affected by the previous SQL command. Note: This does not work on all ODBC connections.

Example:
$db->Sql("SELECT * FROM foo");
print DBG q(# of records: ), $db->RowCount(), qq(\n);

Run stmt

Submit the SQL statement stmt and print data about it. This is used only in debugging.

Example:
$db->Run("SELECT * FROM foo");

See also: Sql

SetMaxBufSize size

Sets the maximum buffer size that a single field can allocate when executing a FetchRow. The default limit is 10240 bytes and the absolute maximum is set to 2147483647 bytes. This absolute maximum can be reset by recompiling the module. Returns undef if successful.

Example:
$newsize = 20480;
$rc = $db->SetMaxBufSize($newsize);
die qq(SetMaxBufSize($newsize) error: ), $db->Error, qq(\n) if ! $rc;

See also: GetMaxBufSize

SetStmtCloseType type

Sets the current ODBC close type setting used by the ODBC Manager. This is used mainly for debugging. Normally, when you open a statement handle and perform a query (or whatever) the results are associated with the statement. You need to free the statement in order to execute another query. When you do this, usually the dataset (from the query) is cached. This caching action may be good for speed but could cause some memory problems if your dataset is huge. See the ODBC API call SQLFreeStmt(hstmt, option) for more details. (All of this is handled automatically by the Win32::ODBC package).

Type will be one of:

• SQL_CLOSE - just close the statement (use caching)
• SQL_DROP - close and drop all results (do not use caching)
• SQL_UNBIND - close and remove bindings to columns (odbc.pll does not bind vars to columns)
• SQL_RESET_PARAMS - close and reset all of the bound parameters (such as type casting for columns; see SQLFreeStmt())

Example:
$oldct = $db->GetStmtCloseType;
$db->SetStmtCloseType(SQL_DROP);
...
$db->SetStmtCloseType($oldct);

See also: GetStmtCloseType

ShutDown

Closes the ODBC connection and print data about it. This is used only in debugging.

Example:
$db->Shutdown;

See also: Close

Sql stmt

Executes the SQL command stmt. Returns undef on success, SQL error code on failure.

Example:
$stmt = "SELECT * FROM foo";
$rc = $db->Sql($stmt);
die qq(SQL failed "$stmt": ), $db->Error(), qq(\n) if $rc;

See also: Error

TableList

TableList qualifier, owner, name, type

Retrieves the list of table names from the current ODBC object using Catalog. If not specified, qualifier and owner default to "", name defaults to "%", and table defaults to "'TABLE'". TableList returns an array of table names. Note:All fieldnames are uppercase!

Example:
@tables = $db->TableList;

See also: Catalog

Examples