DBI pass-thru mode是什么意思？

akwhole

The DBI itself does not mandate or require any particular language to be used; it is language independent. In ODBC terms, the DBI is in "pass-thru" mode, although individual drivers might not be. The only requirement is that queries and other statements must be expressed as a single string of characters passed as the first argument to the "prepare" or "do" methods.

RT。

In ODBC terms, the DBI is in "pass-thru" mode, although individual drivers might not be.

這句不知道在說什么？求大俠賜教。

CPAN鏈接：http://search.cpan.org/~timb/DBI/DBI.pm#SYNOPSIS

jjqing

[quote]The DBI itself does not mandate or require any particular language to be used; it is language indepe ...
[size=2][color=#999999]akwhole 發(fā)表于 2011-08-03 15:58[/color] [url=http://72891.cn/redirect.php?goto=findpost&pid=21287909&ptid=3576313][img]http://72891.cn/images/common/back.gif[/img][/url][/size][/quote]


    意思是說，DBI接口不依賴于具體的數(shù)據(jù)庫類型，它下面有DBD::Oracle, DBD::Mysql來處理這些數(shù)據(jù)庫的差異。

對于DBI來說，它只管把接收到的SQL語句作為一個字符變量，來執(zhí)行prepare和do操作。
my $dsn = "dbi:Oracle:$tns";
my $dbh = DBI->connect( $dsn, $user, $passwd, {RaiseError => 0} );
    my $sql = "SELECT version FROM product_component_version WHERE product LIKE '%Oracle%' ";
    my $sth = $dbh->prepare( $sql );
    $sth->execute( );

數(shù)據(jù)庫的差異由創(chuàng)建$dbh時，由$dsn指定，到了后面的$sth，就只管執(zhí)行SQL。

akwhole

回復(fù) 3# jjqing


    講的很詳細(xì)，多謝 。