Attributes for Handles
This section lists the attribute keys and values that can be
given in many Perl DBI methods, as indicated in the previous section with
%attri
in each method’s syntax. The basic
syntax to set an attribute is
$handle->attribute=>
'setting
‘.
Attribute key/value pairs are separated by commas and are all contained
within a pair of curly braces. For example, to instruct DBI not to return
error messages for a database handle, you would do the following when it’s
created:
my $dbh = DBI->connect('DBI:mysql:bookstore:localhost', 'paola','caporalle1017', {RaiseError=>0});
To retrieve a setting, use
$handle->{attribute}
. This can be stored to
a variable or printed:
print "dbh->{RaiseError=>" . $dbh->{RaiseError} . "}";
If you try this simple line of code, keep in mind that an attribute set to 0 will return an empty value.
Attributes for All Handles
You can use the following attributes with both database handles and statement handles:
Active (boolean, read-only)
This attribute indicates that the handle is active. In the case of a database handle, it indicates that the connection is open. The
disconnect()
method sets this attribute to 0 in a database handle;finish()
sets it to 0 in a statement handle.ActiveKids (integer, read-only)
This attribute provides the number of active handles under the handle that employed the attribute. If called by a driver handle, the number of database handles will be returned. If called by a database handle, the number of active statement handles will ...
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