package DBIx::Class::Storage::DBI;
# -*- mode: cperl; cperl-indent-level: 2 -*-
-use base 'DBIx::Class::Storage';
-
use strict;
use warnings;
+
+use base 'DBIx::Class::Storage';
+use mro 'c3';
+
use Carp::Clan qw/^DBIx::Class/;
use DBI;
use DBIx::Class::Storage::DBI::Cursor;
use List::Util();
__PACKAGE__->mk_group_accessors('simple' =>
- qw/_connect_info _dbi_connect_info _dbh _sql_maker _sql_maker_opts
- _conn_pid _conn_tid transaction_depth _dbh_autocommit savepoints/
+ qw/_connect_info _dbi_connect_info _dbh _sql_maker _sql_maker_opts _conn_pid
+ _conn_tid transaction_depth _dbh_autocommit _driver_determined savepoints/
);
# the values for these accessors are picked out (and deleted) from
}
}
- %attrs = () if (ref $args[0] eq 'CODE'); # _connect() never looks past $args[0] in this case
+ if (ref $args[0] eq 'CODE') {
+ # _connect() never looks past $args[0] in this case
+ %attrs = ()
+ } else {
+ %attrs = (
+ %{ $self->_default_dbi_connect_attributes || {} },
+ %attrs,
+ );
+ }
$self->_dbi_connect_info([@args, keys %attrs ? \%attrs : ()]);
$self->_connect_info;
}
+sub _default_dbi_connect_attributes {
+ return { AutoCommit => 1 };
+}
+
=head2 on_connect_do
This method is deprecated in favour of setting via L</connect_info>.
my $exception = $@;
if(!$exception) { return $want_array ? @result : $result[0] }
- if($tried++ > 0 || $self->connected) {
+ if($tried++ || $self->connected) {
eval { $self->txn_rollback };
my $rollback_exception = $@;
if($rollback_exception) {
sub disconnect {
my ($self) = @_;
- if( $self->connected ) {
+ if( $self->_dbh ) {
my @actions;
push @actions, ( $self->on_disconnect_call || () );
$self->_do_connection_actions(disconnect_call_ => $_) for @actions;
- $self->_dbh->rollback unless $self->_dbh_autocommit;
+ $self->_dbh_rollback unless $self->_dbh_autocommit;
+
$self->_dbh->disconnect;
$self->_dbh(undef);
$self->{_dbh_gen}++;
$sub->();
}
+=head2 connected
+
+=over
+
+=item Arguments: none
+
+=item Return Value: 1|0
+
+=back
+
+Verifies that the the current database handle is active and ready to execute
+an SQL statement (i.e. the connection did not get stale, server is still
+answering, etc.) This method is used internally by L</dbh>.
+
+=cut
+
sub connected {
my ($self) = @_;
=head2 dbh
-Returns the dbh - a data base handle of class L<DBI>.
+Returns a C<$dbh> - a data base handle of class L<DBI>. The returned handle
+is guaranteed to be healthy by implicitly calling L</connected>, and if
+necessary performing a reconnection before returning.
=cut
sub dbh {
my ($self) = @_;
- $self->ensure_connected;
+ if (not $self->_dbh) {
+ $self->_populate_dbh;
+ } else {
+ $self->ensure_connected;
+ }
+ return $self->_dbh;
+}
+
+=head2 last_dbh
+
+This returns the B<last> available C<$dbh> if any, or attempts to
+connect and returns the resulting handle. This method differs from
+L</dbh> by not validating if a preexisting handle is still healthy
+via L</connected>. Make sure you take appropriate precautions
+when using this method, as the C<$dbh> may be useless at this point.
+
+=cut
+
+sub last_dbh {
+ my $self = shift;
+ $self->_populate_dbh unless $self->_dbh;
return $self->_dbh;
}
sub _sql_maker_args {
my ($self) = @_;
- return ( bindtype=>'columns', array_datatypes => 1, limit_dialect => $self->dbh, %{$self->_sql_maker_opts} );
+ return (
+ bindtype=>'columns',
+ array_datatypes => 1,
+ limit_dialect => $self->last_dbh,
+ %{$self->_sql_maker_opts}
+ );
}
sub sql_maker {
sub _populate_dbh {
my ($self) = @_;
+
my @info = @{$self->_dbi_connect_info || []};
$self->_dbh($self->_connect(@info));
# there is no transaction in progress by definition
$self->{transaction_depth} = $self->_dbh_autocommit ? 0 : 1;
+ $self->_run_connection_actions unless $self->{_in_determine_driver};
+}
+
+sub _run_connection_actions {
+ my $self = shift;
my @actions;
push @actions, ( $self->on_connect_call || () );
sub _determine_driver {
my ($self) = @_;
- if (ref $self eq 'DBIx::Class::Storage::DBI') {
- my $driver;
+ if (not $self->_driver_determined) {
+ my $started_unconnected = 0;
+ local $self->{_in_determine_driver} = 1;
+
+ if (ref($self) eq __PACKAGE__) {
+ my $driver;
+ if ($self->_dbh) { # we are connected
+ $driver = $self->_dbh->{Driver}{Name};
+ } else {
+ # try to use dsn to not require being connected, the driver may still
+ # force a connection in _rebless to determine version
+ ($driver) = $self->_dbi_connect_info->[0] =~ /dbi:([^:]+):/i;
+ $started_unconnected = 1;
+ }
- if ($self->_dbh) { # we are connected
- $driver = $self->_dbh->{Driver}{Name};
- } else {
- # try to use dsn to not require being connected, the driver may still
- # force a connection in _rebless to determine version
- ($driver) = $self->_dbi_connect_info->[0] =~ /dbi:([^:]+):/i;
+ my $storage_class = "DBIx::Class::Storage::DBI::${driver}";
+ if ($self->load_optional_class($storage_class)) {
+ mro::set_mro($storage_class, 'c3');
+ bless $self, $storage_class;
+ $self->_rebless();
+ }
}
- my $storage_class = "DBIx::Class::Storage::DBI::${driver}";
- if ($self->load_optional_class($storage_class)) {
- mro::set_mro($storage_class, 'c3');
- bless $self, $storage_class;
- $self->_rebless();
- }
+ $self->_driver_determined(1);
+
+ $self->_run_connection_actions
+ if $started_unconnected && defined $self->_dbh;
}
}
sub txn_begin {
my $self = shift;
- $self->ensure_connected();
if($self->{transaction_depth} == 0) {
$self->debugobj->txn_begin()
if $self->debug;
- # this isn't ->_dbh-> because
- # we should reconnect on begin_work
- # for AutoCommit users
- $self->dbh->begin_work;
- } elsif ($self->auto_savepoint) {
+ $self->_dbh_begin_work;
+ }
+ elsif ($self->auto_savepoint) {
$self->svp_begin;
}
$self->{transaction_depth}++;
}
+sub _dbh_begin_work {
+ my $self = shift;
+ # being here implies we have AutoCommit => 1
+ # if the user is utilizing txn_do - good for
+ # him, otherwise we need to ensure that the
+ # $dbh is healthy on BEGIN
+ my $dbh_method = $self->{_in_dbh_do} ? '_dbh' : 'dbh';
+ $self->$dbh_method->begin_work;
+}
+
sub txn_commit {
my $self = shift;
if ($self->{transaction_depth} == 1) {
my $dbh = $self->_dbh;
$self->debugobj->txn_commit()
if ($self->debug);
- $dbh->commit;
+ $self->_dbh_commit;
$self->{transaction_depth} = 0
if $self->_dbh_autocommit;
}
}
}
+sub _dbh_commit {
+ my $self = shift;
+ $self->_dbh->commit;
+}
+
sub txn_rollback {
my $self = shift;
my $dbh = $self->_dbh;
if ($self->debug);
$self->{transaction_depth} = 0
if $self->_dbh_autocommit;
- $dbh->rollback;
+ $self->_dbh_rollback;
}
elsif($self->{transaction_depth} > 1) {
$self->{transaction_depth}--;
}
}
+sub _dbh_rollback {
+ my $self = shift;
+ $self->_dbh->rollback;
+}
+
# This used to be the top-half of _execute. It was split out to make it
# easier to override in NoBindVars without duping the rest. It takes up
# all of _execute's args, and emits $sql, @bind.
sub insert {
my ($self, $source, $to_insert) = @_;
+# redispatch to insert method of storage we reblessed into, if necessary
+ if (not $self->_driver_determined) {
+ $self->_determine_driver;
+ goto $self->can('insert');
+ }
+
my $ident = $source->from;
my $bind_attributes = $self->source_bind_attributes($source);
my $updated_cols = {};
- $self->ensure_connected;
foreach my $col ( $source->columns ) {
if ( !defined $to_insert->{$col} ) {
my $col_info = $source->column_info($col);
if ( $col_info->{auto_nextval} ) {
- $updated_cols->{$col} = $to_insert->{$col} = $self->_sequence_fetch( 'nextval', $col_info->{sequence} || $self->_dbh_get_autoinc_seq($self->dbh, $source) );
+ $updated_cols->{$col} = $to_insert->{$col} = $self->_sequence_fetch(
+ 'nextval',
+ $col_info->{sequence} ||
+ $self->_dbh_get_autoinc_seq($self->last_dbh, $source)
+ );
}
}
}
@colvalues{@$cols} = (0..$#$cols);
my ($sql, @bind) = $self->sql_maker->insert($table, \%colvalues);
+ $self->_determine_driver;
+
$self->_query_start( $sql, @bind );
my $sth = $self->sth($sql);
sub update {
my $self = shift @_;
my $source = shift @_;
+ $self->_determine_driver;
my $bind_attributes = $self->source_bind_attributes($source);
return $self->_execute('update' => [], $source, $bind_attributes, @_);
sub delete {
my $self = shift @_;
my $source = shift @_;
-
+ $self->_determine_driver;
my $bind_attrs = $self->source_bind_attributes($source);
return $self->_execute('delete' => [], $source, $bind_attrs, @_);
sub _select_args {
my ($self, $ident, $select, $where, $attrs) = @_;
+ my ($alias2source, $rs_alias) = $self->_resolve_ident_sources ($ident);
+
my $sql_maker = $self->sql_maker;
$sql_maker->{_dbic_rs_attrs} = {
%$attrs,
select => $select,
from => $ident,
where => $where,
+ $rs_alias
+ ? ( _source_handle => $alias2source->{$rs_alias}->handle )
+ : ()
+ ,
};
- my ($alias2source, $root_alias) = $self->_resolve_ident_sources ($ident);
-
# calculate bind_attrs before possible $ident mangling
my $bind_attrs = {};
for my $alias (keys %$alias2source) {
my $fqcn = join ('.', $alias, $col);
$bind_attrs->{$fqcn} = $bindtypes->{$col} if $bindtypes->{$col};
- # so that unqualified searches can be bound too
- $bind_attrs->{$col} = $bind_attrs->{$fqcn} if $alias eq $root_alias;
+ # Unqialified column names are nice, but at the same time can be
+ # rather ambiguous. What we do here is basically go along with
+ # the loop, adding an unqualified column slot to $bind_attrs,
+ # alongside the fully qualified name. As soon as we encounter
+ # another column by that name (which would imply another table)
+ # we unset the unqualified slot and never add any info to it
+ # to avoid erroneous type binding. If this happens the users
+ # only choice will be to fully qualify his column name
+
+ if (exists $bind_attrs->{$col}) {
+ $bind_attrs->{$col} = {};
+ }
+ else {
+ $bind_attrs->{$col} = $bind_attrs->{$fqcn};
+ }
}
}
( $attrs->{rows} && keys %{$attrs->{collapse}} )
||
( $attrs->{group_by} && @{$attrs->{group_by}} &&
- $attrs->{prefetch_select} && @{$attrs->{prefetch_select}} )
+ $attrs->{_prefetch_select} && @{$attrs->{_prefetch_select}} )
) {
($ident, $select, $where, $attrs)
= $self->_adjust_select_args_for_complex_prefetch ($ident, $select, $where, $attrs);
my $order = { map
{ $attrs->{$_} ? ( $_ => $attrs->{$_} ) : () }
- (qw/order_by group_by having _virtual_order_by/ )
+ (qw/order_by group_by having/ )
};
return ('select', $attrs->{bind}, $ident, $bind_attrs, $select, $where, $order, @limit);
}
+#
+# This is the code producing joined subqueries like:
+# SELECT me.*, other.* FROM ( SELECT me.* FROM ... ) JOIN other ON ...
+#
sub _adjust_select_args_for_complex_prefetch {
my ($self, $from, $select, $where, $attrs) = @_;
+ $self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute')
+ if (ref $from ne 'ARRAY');
+
# copies for mangling
$from = [ @$from ];
$select = [ @$select ];
$attrs = { %$attrs };
- $self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute')
- if (ref $from ne 'ARRAY');
-
# separate attributes
my $sub_attrs = { %$attrs };
delete $attrs->{$_} for qw/where bind rows offset group_by having/;
- delete $sub_attrs->{$_} for qw/for collapse prefetch_select _collapse_order_by select as/;
+ delete $sub_attrs->{$_} for qw/for collapse _prefetch_select _collapse_order_by select as/;
- my $alias = $attrs->{alias};
+ my $select_root_alias = $attrs->{alias};
+ my $sql_maker = $self->sql_maker;
- # create subquery select list - loop only over primary columns
+ # create subquery select list - consider only stuff *not* brought in by the prefetch
my $sub_select = [];
- for my $i (0 .. @{$attrs->{select}} - @{$attrs->{prefetch_select}} - 1) {
+ my $sub_group_by;
+ for my $i (0 .. @{$attrs->{select}} - @{$attrs->{_prefetch_select}} - 1) {
my $sel = $attrs->{select}[$i];
# alias any functions to the dbic-side 'as' label
# adjust the outer select accordingly
if (ref $sel eq 'HASH' && !$sel->{-select}) {
$sel = { -select => $sel, -as => $attrs->{as}[$i] };
- $select->[$i] = join ('.', $attrs->{alias}, $attrs->{as}[$i]);
+ $select->[$i] = join ('.', $attrs->{alias}, ($attrs->{as}[$i] || "select_$i") );
}
push @$sub_select, $sel;
];
}
- # mangle {from}
- my $select_root = shift @$from;
- my @outer_from = @$from;
+ # mangle {from}, keep in mind that $from is "headless" from here on
+ my $join_root = shift @$from;
my %inner_joins;
my %join_info = map { $_->[0]{-alias} => $_->[0] } (@$from);
- # in complex search_related chains $alias may *not* be 'me'
- # so always include it in the inner join, and also shift away
- # from the outer stack, so that the two datasets actually do
- # meet
- if ($select_root->{-alias} ne $alias) {
- $inner_joins{$alias} = 1;
-
- while (@outer_from && $outer_from[0][0]{-alias} ne $alias) {
- shift @outer_from;
- }
- if (! @outer_from) {
- $self->throw_exception ("Unable to find '$alias' in the {from} stack, something is wrong");
- }
-
- shift @outer_from; # the new subquery will represent this alias, so get rid of it
- }
+ # in complex search_related chains $select_root_alias may *not* be
+ # 'me' so always include it in the inner join
+ $inner_joins{$select_root_alias} = 1 if ($join_root->{-alias} ne $select_root_alias);
# decide which parts of the join will remain on the inside
# It may not be very efficient, but it's a reasonable stop-gap
{
# produce stuff unquoted, so it can be scanned
- my $sql_maker = $self->sql_maker;
local $sql_maker->{quote_char};
+ my $sep = $self->_sql_maker_opts->{name_sep} || '.';
+ $sep = "\Q$sep\E";
my @order_by = (map
{ ref $_ ? $_->[0] : $_ }
);
my $where_sql = $sql_maker->where ($where);
+ my $select_sql = $sql_maker->_recurse_fields ($sub_select);
# sort needed joins
for my $alias (keys %join_info) {
# any table alias found on a column name in where or order_by
# gets included in %inner_joins
# Also any parent joins that are needed to reach this particular alias
- for my $piece ($where_sql, @order_by ) {
- if ($piece =~ /\b$alias\./) {
+ for my $piece ($select_sql, $where_sql, @order_by ) {
+ if ($piece =~ /\b $alias $sep/x) {
$inner_joins{$alias} = 1;
}
}
}
# construct the inner $from for the subquery
- my $inner_from = [ $select_root ];
+ my $inner_from = [ $join_root ];
for my $j (@$from) {
push @$inner_from, $j if $inner_joins{$j->[0]{-alias}};
}
# if a multi-type join was needed in the subquery ("multi" is indicated by
# presence in {collapse}) - add a group_by to simulate the collapse in the subq
-
- for my $alias (keys %inner_joins) {
-
- # the dot comes from some weirdness in collapse
- # remove after the rewrite
- if ($attrs->{collapse}{".$alias"}) {
- $sub_attrs->{group_by} ||= $sub_select;
- last;
+ unless ($sub_attrs->{group_by}) {
+ for my $alias (keys %inner_joins) {
+
+ # the dot comes from some weirdness in collapse
+ # remove after the rewrite
+ if ($attrs->{collapse}{".$alias"}) {
+ $sub_attrs->{group_by} ||= $sub_select;
+ last;
+ }
}
}
$where,
$sub_attrs
);
-
- # put it in the new {from}
- unshift @outer_from, {
- -alias => $alias,
- -source_handle => $select_root->{-source_handle},
- $alias => $subq,
+ my $subq_joinspec = {
+ -alias => $select_root_alias,
+ -source_handle => $join_root->{-source_handle},
+ $select_root_alias => $subq,
};
+ # Generate a new from (really just replace the join slot with the subquery)
+ # Before we would start the outer chain from the subquery itself (i.e.
+ # SELECT ... FROM (SELECT ... ) alias JOIN ..., but this turned out to be
+ # a bad idea for search_related, as the root of the chain was effectively
+ # lost (i.e. $artist_rs->search_related ('cds'... ) would result in alias
+ # of 'cds', which would prevent from doing things like order_by artist.*)
+ # See t/prefetch/via_search_related.t for a better idea
+ my @outer_from;
+ if ($join_root->{-alias} eq $select_root_alias) { # just swap the root part and we're done
+ @outer_from = (
+ $subq_joinspec,
+ @$from,
+ )
+ }
+ else { # this is trickier
+ @outer_from = ($join_root);
+
+ for my $j (@$from) {
+ if ($j->[0]{-alias} eq $select_root_alias) {
+ push @outer_from, [
+ $subq_joinspec,
+ @{$j}[1 .. $#$j],
+ ];
+ }
+ else {
+ push @outer_from, $j;
+ }
+ }
+ }
+
# This is totally horrific - the $where ends up in both the inner and outer query
# Unfortunately not much can be done until SQLA2 introspection arrives, and even
# then if where conditions apply to the *right* side of the prefetch, you may have
my ($self, $ident) = @_;
my $alias2source = {};
- my $root_alias;
+ my $rs_alias;
# the reason this is so contrived is that $ident may be a {from}
# structure, specifying multiple tables to join
if ( Scalar::Util::blessed($ident) && $ident->isa("DBIx::Class::ResultSource") ) {
# this is compat mode for insert/update/delete which do not deal with aliases
$alias2source->{me} = $ident;
- $root_alias = 'me';
+ $rs_alias = 'me';
}
elsif (ref $ident eq 'ARRAY') {
my $tabinfo;
if (ref $_ eq 'HASH') {
$tabinfo = $_;
- $root_alias = $tabinfo->{-alias};
+ $rs_alias = $tabinfo->{-alias};
}
if (ref $_ eq 'ARRAY' and ref $_->[0] eq 'HASH') {
$tabinfo = $_->[0];
}
}
- return ($alias2source, $root_alias);
+ return ($alias2source, $rs_alias);
}
# Takes $ident, \@column_names
# also note: this adds -result_source => $rsrc to the column info
#
# usage:
-# my $col_sources = $self->_resolve_column_info($ident, [map $_->[0], @{$bind}]);
+# my $col_sources = $self->_resolve_column_info($ident, @column_names);
sub _resolve_column_info {
my ($self, $ident, $colnames) = @_;
my ($alias2src, $root_alias) = $self->_resolve_ident_sources($ident);
my $sep = $self->_sql_maker_opts->{name_sep} || '.';
$sep = "\Q$sep\E";
- my (%return, %converted);
+ my (%return, %seen_cols);
+
+ # compile a global list of column names, to be able to properly
+ # disambiguate unqualified column names (if at all possible)
+ for my $alias (keys %$alias2src) {
+ my $rsrc = $alias2src->{$alias};
+ for my $colname ($rsrc->columns) {
+ push @{$seen_cols{$colname}}, $alias;
+ }
+ }
+
+ COLUMN:
foreach my $col (@$colnames) {
my ($alias, $colname) = $col =~ m/^ (?: ([^$sep]+) $sep)? (.+) $/x;
- # deal with unqualified cols - we assume the main alias for all
- # unqualified ones, ugly but can't think of anything better right now
- $alias ||= $root_alias;
+ unless ($alias) {
+ # see if the column was seen exactly once (so we know which rsrc it came from)
+ if ($seen_cols{$colname} and @{$seen_cols{$colname}} == 1) {
+ $alias = $seen_cols{$colname}[0];
+ }
+ else {
+ next COLUMN;
+ }
+ }
my $rsrc = $alias2src->{$alias};
- $return{$col} = $rsrc && { %{$rsrc->column_info($colname)}, -result_source => $rsrc };
+ $return{$col} = $rsrc && {
+ %{$rsrc->column_info($colname)},
+ -result_source => $rsrc,
+ -source_alias => $alias,
+ };
}
+
return \%return;
}
return @pcols ? \@pcols : [ 1 ];
}
+#
+# Returns an ordered list of column names before they are used
+# in a SELECT statement. By default simply returns the list
+# passed in.
+#
+# This may be overridden in a specific storage when there are
+# requirements such as moving BLOB columns to the end of the
+# SELECT list.
+sub _order_select_columns {
+ #my ($self, $source, $columns) = @_;
+ return @{$_[2]};
+}
+
+
+
sub source_bind_attributes {
my ($self, $source) = @_;
=cut
-sub sqlt_type { shift->dbh->{Driver}->{Name} }
+sub sqlt_type { shift->last_dbh->{Driver}->{Name} }
=head2 bind_attribute_by_data_type
sub deployment_statements {
my ($self, $schema, $type, $version, $dir, $sqltargs) = @_;
# Need to be connected to get the correct sqlt_type
- $self->ensure_connected() unless $type;
+ $self->last_dbh() unless $type;
$type ||= $self->sqlt_type;
$version ||= $schema->schema_version || '1.x';
$dir ||= './';
return if $line =~ /^\s+$/; # skip whitespace only
$self->_query_start($line);
eval {
- $self->dbh->do($line); # shouldn't be using ->dbh ?
+ # a previous error may invalidate $dbh - thus we need to use dbh()
+ # to guarantee a healthy $dbh (this is temporary until we get
+ # proper error handling on deploy() )
+ $self->dbh->do($line);
};
if ($@) {
carp qq{$@ (running "${line}")};
sub datetime_parser {
my $self = shift;
return $self->{datetime_parser} ||= do {
- $self->ensure_connected;
+ $self->last_dbh;
$self->build_datetime_parser(@_);
};
}
DBIx::Class can do some wonderful magic with handling exceptions,
disconnections, and transactions when you use C<< AutoCommit => 1 >>
-combined with C<txn_do> for transaction support.
+(the default) combined with C<txn_do> for transaction support.
If you set C<< AutoCommit => 0 >> in your connect info, then you are always
in an assumed transaction between commits, and you're telling us you'd
be with raw DBI.
-
=head1 AUTHORS
Matt S. Trout <mst@shadowcatsystems.co.uk>