59 lines
1.8 KiB
Plaintext
59 lines
1.8 KiB
Plaintext
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What you achieve with MysqlPerl
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MysqlPerl is an interface between the perl programming language and the
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MySQL programming API that comes with the MySQL relational database
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management system. All functions provided by the MySQL programming API
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are supported.
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From perl you activate the interface with the statement
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use Mysql;
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After that you can connect to multiple msql database servers and send
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multiple queries to any of them via an simple object oriented
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interface. Two types of objects are available: database handles and
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statement handles. Perl returns a database handle to the Connect
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method like so:
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$dbh = Mysql->connect($hostname,$databasename);
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Once you have connected to a database, you get a statement handle
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with:
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$sth = $dbh->query("select foo from bar");
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You can open as many queries as you like simultaneously by selecting a
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different scalar to hold the object:
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$another_sth = $dbh->Query("select bar from foo");
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The statement handle allows you to step through the virtual table
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returned from the database with the FetchRow method:
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@row = $sth->fetchrow;
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or
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%hash = $sth->fetchhash;
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You can access all metadata that MySQL supplies for a given table. To
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find out the number of rows or the number of fields returned by a
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query you simply say:
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$numrows = $sth->numrows;
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$numfields = $sth->numfields;
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To find out the size in bytes for the field with the offset 0 (the
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first field of a query), you say:
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$length = $sth->length->[0];
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The list of the names for each column is returned by
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@list => $sth->name;
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As for other metadata available, consult the manpage that comes with
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MysqlPerl and study the examples in the file t/msql.t, which is the
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extensive testscript to test your installation, but is heavily
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commented, so you may use it as a tutorial.
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