[ViewVC] Diff of: cvs/PApp-SQL/SQL.pm

Comparing PApp-SQL/SQL.pm (file contents):
Revision 1.12 by root, Mon Feb 12 17:47:10 2001 UTC vs.
Revision 1.40 by root, Mon Feb 13 05:59:55 2012 UTC

 =head1 NAME
-PApp::SQL - absolutely easy yet fast and powerful sql access
+PApp::SQL - absolutely easy yet fast and powerful sql access.
 =head1 SYNOPSIS
  use PApp::SQL;
  my $st = sql_exec $DBH, "select ... where a = ?", $a;
  local $DBH = <database handle>;
  my $st = sql_exec \my($bind_a, $bind_b), "select a,b ...";
- my $st = sql_insertid
+ my $id = sql_insertid
              sql_exec "insert into ... values (?, ?)", $v1, $v2;
  my $a = sql_fetch "select a from ...";
  sql_fetch \my($a, $b), "select a,b ...";
- sql_exists "name from table where name like 'a%'"
+ sql_exists "table where name like 'a%'"
     or die "a* required but not existent";
  my $db = new PApp::SQL::Database "", "DBI:mysql:test", "user", "pass";
  local $PApp::SQL::DBH = $db->checked_dbh; # does 'ping'
 This module provides you with easy-to-use functions to execute sql
 commands (using DBI). Despite being easy to use, they are also quite
 efficient and allow you to write faster programs in less lines of code. It
 should work with anything from perl-5.004_01 onwards, but I only support
-5.005+.
+5.005+. UTF8 handling (the C<sql_u*> family of functions) will only be
+effective with perl version 5.006 and beyond.
 If the descriptions here seem terse or if you always wanted to know
 what PApp is then have a look at the PApp module which uses this module
 extensively but also provides you with a lot more gimmicks to play around
 with to help you create cool applications ;)
 =cut
 package PApp::SQL;
+use Carp ();
 use DBI ();
 BEGIN {
    use base qw(Exporter DynaLoader);
-   $VERSION = 0.121;
+   $VERSION = '2.0';
    @EXPORT = qw(
-         sql_exec sql_fetch sql_fetchall sql_exists sql_insertid $sql_exec
+         sql_exec  sql_fetch  sql_fetchall  sql_exists sql_insertid $sql_exec
+         sql_uexec sql_ufetch sql_ufetchall sql_uexists
    );
    @EXPORT_OK = qw(
          connect_cached
    );
    bootstrap PApp::SQL $VERSION;
 }
+boot2 DBI::SQL_VARCHAR, DBI::SQL_INTEGER, DBI::SQL_DOUBLE;
 our $sql_exec;  # last result of sql_exec's execute call
 our $DBH;       # the default database handle
 our $Database;	# the current SQL::Database object, if applicable
 our %dbcache;
-=head2 GLOBAL VARIABLES
+=head2 Global Variables
 =over 4
 =item $sql_exec
 Since the C<sql_exec> family of functions return a statement handle there
-must eb another way to test the return value of the C<execute> call. This
+must be another way to test the return value of the C<execute> call. This
 global variable contains the result of the most recent call to C<execute>
 done by this module.
 =item $PApp::SQL::DBH
 The default database handle used by this module if no C<$DBH> was
-specified as argument and no C<$DBH> is found in the current package. See
+specified as argument. See C<sql_exec> for a discussion.
-C<sql_exec> for a discussion.
 =item $PApp::SQL::Database
 The current default C<PApp::SQL::Database>-object. Future versions might
 automatically fall back on this database and create database handles from
 be nice as a placeholder for the database object that corresponds to
 $PApp::SQL::DBH.
 =back
-=head2 FUNCTIONS
+=head2 Functions
 =over 4
 =item $dbh = connect_cached $id, $dsn, $user, $pass, $flags, $connect
 __LINE__ work fine as well).
 The reason C<$id> is necessary is that you might specify special connect
 arguments or special flags, or you might want to configure your $DBH
 differently than maybe other applications requesting the same database
-connection. If none of this is becessary for your application you can
+connection. If none of this is necessary for your application you can
-leave $id empty (i.e. "").
+leave C<$id> empty (i.e. "").
 If specified, C<$connect> is a callback (e.g. a coderef) that will be
 called each time a new connection is being established, with the new
 C<$dbh> as first argument.
 Examples:
  # try your luck opening the papp database without access info
  $dbh = connect_cached __FILE__, "DBI:mysql:papp";
+Mysql-specific behaviour: The default setting of
+C<mysql_client_found_rows> is TRUE, you can overwrite this, though.
 =cut
 sub connect_cached {
    my ($id, $dsn, $user, $pass, $flags, $connect) = @_;
    # the following line is duplicated in PApp::SQL::Database::new
    $id = "$id\0$dsn\0$user\0$pass";
    unless ($dbcache{$id} && $dbcache{$id}->ping) {
-      #warn "connecting to ($dsn|$user|$pass|$flags)\n";#d#
       # first, nuke our statement cache (sooory ;)
       cachesize cachesize 0;
+      # then make mysql behave more standardly by default
+      $dsn =~ /^[Dd][Bb][Ii]:mysql:/
+         and $dsn !~ /;mysql_client_found_rows/
+            and $dsn .= ";mysql_client_found_rows=1";
       # then connect anew
       $dbcache{$id} =
          eval { DBI->connect($dsn, $user, $pass, $flags) }
          || eval { DBI->connect($dsn, $user, $pass, $flags) }
-         || die "unable to connect to database $dsn: $DBI::errstr\n";
+         || Carp::croak "unable to connect to database $dsn: $DBI::errstr\n";
       $connect->($dbcache{$id}) if $connect;
    }
    $dbcache{$id};
 }
 =item $sth = sql_exec [dbh,] [bind-vals...,] "sql-statement", [arguments...]
+=item $sth = sql_uexec <see sql_exec>
 C<sql_exec> is the most important and most-used function in this module.
 Runs the given sql command with the given parameters and returns the
 statement handle. The command and the statement handle will be cached
 (with the database handle and the sql string as key), so prepare will be
 called only once for each distinct sql call (please keep in mind that the
 returned statement will always be the same, so, if you call C<sql_exec>
 with the same dbh and sql-statement twice (e.g. in a subroutine you
-called), the statement handle for the first call mustn't be used.
+called), the statement handle for the first call mustn't not be in use
+anymore, as the subsequent call will re-use the handle.
 The database handle (the first argument) is optional. If it is missing,
-C<sql_exec> first tries to use the variable C<$DBH> in the current (=
+it tries to use database handle in C<$PApp::SQL::DBH>, which you can set
-calling) package and, if that fails, it tries to use database handle in
+before calling these functions. NOTICE: future and former versions of
-C<$PApp::SQL::DBH>, which you can set before calling these functions.
+PApp::SQL might also look up the global variable C<$DBH> in the callers
+package.
+=begin comment
+If it is missing, C<sql_exec> first tries to use the variable C<$DBH>
+in the current (= calling) package and, if that fails, it tries to use
+database handle in C<$PApp::SQL::DBH>, which you can set before calling
+these functions.
+=end comment
 The actual return value from the C<$sth->execute> call is stored in the
 package-global (and exported) variable C<$sql_exec>.
 If any error occurs C<sql_exec> will throw an exception.
+C<sql_uexec> is similar to C<sql_exec> but upgrades all input arguments to
+UTF-8 before calling the C<execute> method.
 Examples:
  # easy one
  my $st = sql_exec "select name, id from table where id = ?", $id;
  sql_exec $dbh, "update file set name = ?", "oops.txt";
 =item sql_fetch <see sql_exec>
+=item sql_ufetch <see sql_uexec>
-Execute a sql-statement and fetch the first row of results. Depending on
+Execute an sql-statement and fetch the first row of results. Depending on
 the caller context the row will be returned as a list (array context), or
 just the first columns. In table form:
  CONTEXT	RESULT
  void		()
  my($name, $amount) = sql_fetch "select ...", args...
 ... and it's still quite fast unless you fetch large amounts of data.
+C<sql_ufetch> is similar to C<sql_fetch> but upgrades all input values to
+UTF-8 and forces all result values to UTF-8 (this does I<not> include result
+parameters, only return values. Using bind variables in conjunction with
+sql_u* functions might result in undefined behaviour - we use UTF-8 on
+bind-variables at execution time and it seems to work on DBD::mysql as it
+ignores the UTF-8 bit completely. Which just means that that DBD-driver is
+broken).
 =item sql_fetchall <see sql_exec>
+=item sql_ufetchall <see sql_uexec>
 Similarly to C<sql_fetch>, but all result rows will be fetched (this is
 of course inefficient for large results!). The context is ignored (only
 list context makes sense), but the result still depends on the number of
 columns in the result:
  for (sql_fetchall "select name, age, place from user") {
     my ($name, $age, $place) = @$_;
  }
+C<sql_ufetchall> is similar to C<sql_fetchall> but upgrades all input
+values to UTF-8 and forces all result values to UTF-8 (see the caveats in
+the description of C<sql_ufetch>, though).
-=item sql_exists "<table> where ...", args...
+=item sql_exists "<table_references> where <where_condition>...", args...
+=item sql_uexists <see sql_exists>
 Check wether the result of the sql-statement "select xxx from
 $first_argument" would be empty or not (that is, imagine the string
-"select from" were prepended to your statement (it isn't)). Should work
+"select * from" were prepended to your statement (it isn't)). Should work
 with every database but can be quite slow, except on mysql, where this
 should be quite fast.
+C<sql_uexists> is similar to C<sql_exists> but upgrades all parameters to
+UTF-8.
 Examples:
  print "user 7 exists!\n"
     if sql_exists "user where id = ?", 7;
  mysql:    first C<AUTO_INCREMENT> column set to NULL
  postgres: C<oid> column (is there a way to get the last SERIAL?)
  sybase:   C<IDENTITY> column of the last insert (slow)
  informix: C<SERIAL> or C<SERIAL8> column of the last insert
+ sqlite:   C<last_insert_rowid()>
 Except for sybase, this does not require a server access.
 =cut
 sub sql_insertid($) {
-   my $sth = shift or die "sql_insertid requires a statement handle";
+   my $sth = shift or Carp::croak "sql_insertid requires a statement handle";
    my $dbh = $sth->{Database};
    my $driver = $dbh->{Driver}{Name};
    $driver eq "mysql"    and return $sth->{mysql_insertid};
    $driver eq "Pg"       and return $sth->{pg_oid_status};
-   $driver eq "Sybase"   and return sql_fetch($dbh, 'SELECT @@IDENTITY');
+   $driver eq "Sybase"   and return sql_fetch ($dbh, 'SELECT @@IDENTITY');
    $driver eq "Informix" and return $sth->{ix_sqlerrd}[1];
+   $driver eq "SQLite"   and return sql_fetch ($dbh, 'SELECT last_insert_rowid ()');
-   die "sql_insertid does not spport the dbd driver '$driver', please see PApp::SQL::sql_insertid";
+   Carp::croak "sql_insertid does not support the dbd driver '$driver', at";
 }
 =item [old-size] = cachesize [new-size]
 Returns (and possibly changes) the LRU cache size used by C<sql_exec>. The
 default is somewhere around 50 (= the 50 last recently used statements
-will be cached). It shouldn't be too large, since a simple linear listed
+will be cached). It shouldn't be too large, since a simple linear list
 is used for the cache at the moment (which, for small (<100) cache sizes
 is actually quite fast).
 The function always returns the cache size in effect I<before> the call,
 so, to nuke the cache (for example, when a database connection has died
 =cut
 reinitialize;
+=head2 Type Deduction
+Since every database driver seems to deduce parameter types differently,
+usually wrongly, and at leats in the case of DBD::mysql, different in
+every other release or so, and this can and does lead to data corruption,
+this module does type deduction itself.
+What does it mean? Simple - sql parameters for placeholders will be
+explicitly marked as SQL_VARCHAR, SQL_INTEGER or SQL_DOUBLE the first time
+a statement is prepared.
+To force a specific type, you can either continue to use e.g. sql casts,
+or you can make sure to consistently use strings or numbers. To make a
+perl scalar look enough like a string or a number, use this when passing
+it to sql_exec or a similar functions:
+   "$string"   # to pass a string
+   $num+0      # to pass a number
+=cut
 package PApp::SQL::Database;
-=head2 THE DATABASE CLASS
+=head2 The Database Class
-Again (sigh) the problem of persistency. What do you do when you have to serialize on object
+Again (sigh) the problem of persistency. What do you do when you have
-that contains (or should contain) a database handle? Short answer: you don't. Long answer:
+to serialize on object that contains (or should contain) a database
+handle? Short answer: you don't. Long answer: you can embed the necessary
-you can embed the necessary information to recreate the dbh when needed.
+information to recreate the dbh when needed.
 The C<PApp::SQL::Database> class does that, in a relatively efficient
 fashion: the overhead is currently a single method call per access (you
 can cache the real dbh if you want).
 sub checked_dbh($) {
    my $dbh = $dbcache{$_[0][0]};
    $dbh && $dbh->ping
       ? $dbh
-      : PApp::SQL::connect_cached((split /\x00/, $_[0][0]), $_[0][1], $_[0][2]);
+      : PApp::SQL::connect_cached((split /\x00/, $_[0][0], 4), $_[0][1], $_[0][2]);
 }
 =item $db->dsn
 Return the DSN (L<DBI>) fo the database object (e.g. for error messages).
+=item $db->login
+Return the login name.
+=item $db->password
+Return the password (emphasizing the fact that the password is stored plaintext ;)
 =cut
 sub dsn($) {
    my $self = shift;
    (split /\x00/, $self->[0])[1];
 }
+sub login($) {
+   my $self = shift;
+   (split /\x00/, $self->[0])[2];
+}
+sub password($) {
+   my $self = shift;
+   (split /\x00/, $self->[0])[3];
+}
 =back
 =cut
 1;
 L<PApp>.
 =head1 AUTHOR
- Marc Lehmann <pcg@goof.com>
+ Marc Lehmann <schmorp@schmorp.de>
- http://www.goof.com/pcg/marc/
+ http://home.schmorp.de/
 =cut

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Comparing PApp-SQL/SQL.pm (file contents): Revision 1.12 by root, Mon Feb 12 17:47:10 2001 UTC vs. Revision 1.40 by root, Mon Feb 13 05:59:55 2012 UTC

Diff Legend

Comparing PApp-SQL/SQL.pm (file contents):
Revision 1.12 by root, Mon Feb 12 17:47:10 2001 UTC vs.
Revision 1.40 by root, Mon Feb 13 05:59:55 2012 UTC