NAME

Data::Direct - Perl module to emulate seqeuntial access to SQL tables.

SYNOPSIS

In a script:

use Data::Direct;

$dd = new Data::Direct("dbi:Informix:FBI", "bill_c", "M0n|c4", "porn_suppliers", "PRICE < 99.99", "ORDER BY PUBLICATION_DATE" || die "Failed to connect";

Last two arguments can be ommitted.

        while (!$dd->eof) { 
                        # Iterate over all records
        if ($dd{'LAST_MODIFIED'}) {
                $dd->delete;            
                        # Mark RIP flag
                next;
        }                               
                        # Change fields
        $dd->{'KILL'}++ if ($dd->{'REVENUE'} > 199.99);
        $dd->update;                    
                        # Update record in memory
        $dd->next;                      
                        # Goto next record
}

$dd->addnew; # Add a new record $dd->{'PRICE'} = 999.99; $dd->{'KILL'} = 0; $dd->{'REVENUE'} = 199.99; $dd->update; # Update new record in memory

$dd->flush; # Rewrite table

From the command prompt:

prompt % perl -MData::Direct -e 'edit("dbi::XBase::/var/db/files", "contacts");'

prompt % perl -MData::Direct -e 'edit("dbi::Oracle::CIA", "weapons");' /U 'bill_c' /P 'M0n1c4' /W "EXPIRES <= SYS_DATE()" /A "GROUP BY PRICE"

DESCRIPTION

Data::Direct selects rows from a table and lets you updated them in a memory array. Upon calling the flush method, it erases the records from the table and inserts them from the array. You can supply a WHERE filter to be applied both on query and on deletion, and additional SQL code for sorting the records.

OPTIONS

Constructor

new($dsn, $user, $pass, $table [, $where_clause [, $additional_select_code]] Connects to the DBI DSN specified, using #user and $pass. $where_clause and $additional_select_code will be added to your SQL code. After that, reads all the records to memory.

Navigating

next

Fetches the next record. Returns undef if gone past end.

back

Fetches the previous record. Returns undef if gone past beginning.

eof

Returns true if cursor is after all the records.

bof

Simillar, checks beginning of table.

recs

Returns the number of records in the buffer

rows

Returns the number of records in the buffer which are not deleted. recs and rows are not the same!

setbookmark($name)

Sets a named bookmark, to be used for gotobookmark.

gotobookmark($name)

Takes the cursor to the specific bookmark.

fetch($rownumber)

Retrieve a numbered record.

cursor

Returns the row number the cursor is at.

Manipulating records

bind($column => \$var, $column => \$var...)

Binds a column to a scalar, using a scalar reference.

bindsimple($package)

Binds each column to a variable with the same name, under the package given. Use bindsimple with no parameters to bind to the main namespace.

update

Update record after fields have been changed by accessing the members of the object or the bound variables.

addnew

Add a new record and point the cursor on it.

delete

Mark a record for deletion.

undelete

Unmark a record for deletion.

isdeleted

Check if a record is marked for deletion.

Automatic editing

spawn($editor, $packing_instructions, $unpacking_instructions)

Writes a text file where every line represents a record, launch the process $editor, then update the table with the saved file. Records are serialized and deserialized by the code references in the last parameters.

$dd->spawn("grep <-v> <-i> Bill", sub {join(":", @_);}, sub {my $l = <$_>; chop $l; split(/:/, $l);});

spawn($editor, $delimiter)

Uses the string as a delimiter to serialize and deserialize records.

spawn($editor)

Uses CSV format to serialize and deserialize records.

spawn

Launches vi or whatever $ENV{'EDITOR'} points to as an editor.

AUTHOR

Ariel Brosh, schop@cpan.org

SEE ALSO

DBI.