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Posted on 2000-04-23
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Last Modified: 2010-03-05
how can I get the total number of records in a table of a database?
i would like to use PERL, DBI.
any one can provide me a simple source code?

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Question by:stanleyhuen
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Accepted Solution

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yovavm101799 earned 10 total points
ID: 2741744
1. Connect to your DB.

2. Perform a 'select* from Table'

3. Get the meta-data $DBI::rows
This variable holds the number of rows affected or returned by the last executed statement

Sample:
------
use DBI;
$dbname = 'DEMO'; $user = 'admin';
$password = 'pass'; $dbd = 'Oracle';

$dbh = DBI->connect($dbname,$user,$password,$dbd) ||
       die "Error connecting $DBI::errstr\n";;


$sth = $dbh->prepare("Select * from Customers");
if ($DBI::err) {
  die STDERR "$DBI::errstr\n";
}
$sth->execute() ;
if ($DBI::err) {
  die STDERR "$DBI::errstr\n";
}
$numOfRecs = $DBI::rows;
print "Total records in table: Customer is $numOfRecs\n";


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Expert Comment

by:mwhuen
ID: 2741967
besides  $DBI::rows, $DBI::err, $DBI::errstr, any other useful functions of DBI?
where can I get more information of these useful functions?
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Expert Comment

by:yovavm101799
ID: 2743055
In case you mean MetaData, well here are some methods used to obtain Meta Data:

$dbh->tables()
fetch a list of all accessible table names

$DBI::rows
The number of rows affected or returned

After executing the statement, use the statement handle to get:

$sth->{NUM_FIELDS}
The number of fields returned by a select

$sth->{NUM_PARAMS}
The number of parameters returned by any query

After a select query, the following attributes contain references to arrays of field-specific information:

$sth->{NAME}
Column names returned by the query

$sth->{NULLABLE}
Booleans indicating whether fields are nullable or not

$sth->{TYPE}
Field types

$sth->{PRECISION}
Floating-point precision of field

$sth->{SCALE}
Field lengths

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Author Comment

by:stanleyhuen
ID: 2744498
thanks yovavm,

i would like to learn more about DBI?

do u know any good resources of DBI?
0
 

Expert Comment

by:yovavm101799
ID: 2746477
Check: "Advanced Perl Programming", By Sriram Srinivasan, published by O'Reilly & Associates.
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