#
# This module contains code that should never have seen the light of day,
# does not belong in the Storage, or is otherwise unfit for public
-# display. The arrival of SQLA2 should immediately oboslete 90% of this
+# display. The arrival of SQLA2 should immediately obsolete 90% of this
#
use strict;
use base 'DBIx::Class::Storage';
use mro 'c3';
-use Carp::Clan qw/^DBIx::Class/;
+use List::Util 'first';
+use Scalar::Util 'blessed';
+use Sub::Name 'subname';
+use namespace::clean;
#
# This code will remove non-selecting/non-restricting joins from
# {from} specs, aiding the RDBMS query optimizer
#
sub _prune_unused_joins {
- my ($self) = shift;
-
+ my $self = shift;
my ($from, $select, $where, $attrs) = @_;
+ return $from unless $self->_use_join_optimizer;
+
if (ref $from ne 'ARRAY' || ref $from->[0] ne 'HASH' || ref $from->[1] ne 'ARRAY') {
return $from; # only standard {from} specs are supported
}
# {multiplying} joins can go
delete $aliastypes->{multiplying} if $attrs->{group_by};
-
my @newfrom = $from->[0]; # FROM head is always present
- my %need_joins = (map { %{$_||{}} } (values %$aliastypes) );
+ my %need_joins;
+ for (values %$aliastypes) {
+ # add all requested aliases
+ $need_joins{$_} = 1 for keys %$_;
+
+ # add all their parents (as per joinpath which is an AoH { table => alias })
+ $need_joins{$_} = 1 for map { values %$_ } map { @$_ } values %$_;
+ }
for my $j (@{$from}[1..$#$from]) {
push @newfrom, $j if (
(! $j->[0]{-alias}) # legacy crap
#
# This is the code producing joined subqueries like:
-# SELECT me.*, other.* FROM ( SELECT me.* FROM ... ) JOIN other ON ...
+# SELECT me.*, other.* FROM ( SELECT me.* FROM ... ) JOIN other ON ...
#
sub _adjust_select_args_for_complex_prefetch {
my ($self, $from, $select, $where, $attrs) = @_;
$self->throw_exception ('Nothing to prefetch... how did we get here?!')
- if not @{$attrs->{_prefetch_select}};
+ if not @{$attrs->{_prefetch_selector_range}};
$self->throw_exception ('Complex prefetches are not supported on resultsets with a custom from attribute')
if (ref $from ne 'ARRAY' || ref $from->[0] ne 'HASH' || ref $from->[1] ne 'ARRAY');
my $outer_attrs = { %$attrs };
delete $outer_attrs->{$_} for qw/where bind rows offset group_by having/;
- my $inner_attrs = { %$attrs };
- delete $inner_attrs->{$_} for qw/for collapse _prefetch_select _collapse_order_by select as/;
+ my $inner_attrs = { %$attrs, _is_internal_subuery => 1 };
+ delete $inner_attrs->{$_} for qw/for collapse _prefetch_selector_range _collapse_order_by select as/;
# bring over all non-collapse-induced order_by into the inner query (if any)
# the outer one will have to keep them all
delete $inner_attrs->{order_by};
- if (my $ord_cnt = @{$outer_attrs->{order_by}} - @{$outer_attrs->{_collapse_order_by}} ) {
+ if (my $ord_cnt = @{$outer_attrs->{order_by}} - @{$outer_attrs->{_collapse_order_by}||[]} ) {
$inner_attrs->{order_by} = [
@{$outer_attrs->{order_by}}[ 0 .. $ord_cnt - 1]
];
# on the outside we substitute any function for its alias
my $outer_select = [ @$select ];
my $inner_select = [];
- for my $i (0 .. ( @$outer_select - @{$outer_attrs->{_prefetch_select}} - 1) ) {
+
+ my ($p_start, $p_end) = @{$outer_attrs->{_prefetch_selector_range}};
+ for my $i (0 .. $p_start - 1, $p_end + 1 .. $#$outer_select) {
my $sel = $outer_select->[$i];
if (ref $sel eq 'HASH' ) {
}
push @$inner_select, $sel;
+
+ push @{$inner_attrs->{as}}, $attrs->{as}[$i];
}
- # construct the inner $from for the subquery
+ # construct the inner $from and lock it in a subquery
# we need to prune first, because this will determine if we need a group_by below
- my $inner_from = $self->_prune_unused_joins ($from, $inner_select, $where, $inner_attrs);
-
- # if a multi-type join was needed in the subquery - add a group_by to simulate the
- # collapse in the subq
- $inner_attrs->{group_by} ||= $inner_select
- if List::Util::first
- { ! $_->[0]{-is_single} }
- (@{$inner_from}[1 .. $#$inner_from])
- ;
+ # the fake group_by is so that the pruner throws away all non-selecting, non-restricting
+ # multijoins (since we def. do not care about those inside the subquery)
+
+ my $inner_subq = do {
+
+ # must use it here regardless of user requests
+ local $self->{_use_join_optimizer} = 1;
+
+ my $inner_from = $self->_prune_unused_joins ($from, $inner_select, $where, {
+ group_by => ['dummy'], %$inner_attrs,
+ });
+
+ my $inner_aliastypes =
+ $self->_resolve_aliastypes_from_select_args( $inner_from, $inner_select, $where, $inner_attrs );
+
+ # we need to simulate collapse in the subq if a multiplying join is pulled
+ # by being a non-selecting restrictor
+ if (
+ ! $inner_attrs->{group_by}
+ and
+ first {
+ $inner_aliastypes->{restricting}{$_}
+ and
+ ! $inner_aliastypes->{selecting}{$_}
+ } ( keys %{$inner_aliastypes->{multiplying}||{}} )
+ ) {
+ my $unprocessed_order_chunks;
+ ($inner_attrs->{group_by}, $unprocessed_order_chunks) = $self->_group_over_selection (
+ $inner_from, $inner_select, $inner_attrs->{order_by}
+ );
+
+ $self->throw_exception (
+ 'A required group_by clause could not be constructed automatically due to a complex '
+ . 'order_by criteria. Either order_by columns only (no functions) or construct a suitable '
+ . 'group_by by hand'
+ ) if $unprocessed_order_chunks;
+ }
- # generate the subquery
- my $subq = $self->_select_args_to_query (
- $inner_from,
- $inner_select,
- $where,
- $inner_attrs,
- );
+ # we already optimized $inner_from above
+ local $self->{_use_join_optimizer} = 0;
- my $subq_joinspec = {
- -alias => $attrs->{alias},
- -source_handle => $inner_from->[0]{-source_handle},
- $attrs->{alias} => $subq,
+ # generate the subquery
+ $self->_select_args_to_query (
+ $inner_from,
+ $inner_select,
+ $where,
+ $inner_attrs,
+ );
};
# Generate the outer from - this is relatively easy (really just replace
# - it is part of the restrictions, in which case we need to collapse the outer
# result by tackling yet another group_by to the outside of the query
- # normalize a copy of $from, so it will be easier to work with further
- # down (i.e. promote the initial hashref to an AoH)
$from = [ @$from ];
- $from->[0] = [ $from->[0] ];
# so first generate the outer_from, up to the substitution point
my @outer_from;
while (my $j = shift @$from) {
+ $j = [ $j ] unless ref $j eq 'ARRAY'; # promote the head-from to an AoH
+
if ($j->[0]{-alias} eq $attrs->{alias}) { # time to swap
+
push @outer_from, [
- $subq_joinspec,
+ {
+ -alias => $attrs->{alias},
+ -rsrc => $j->[0]{-rsrc},
+ $attrs->{alias} => $inner_subq,
+ },
@{$j}[1 .. $#$j],
];
last; # we'll take care of what's left in $from below
}
}
- # scan the from spec against different attributes, and see which joins are needed
+ # scan the *remaining* from spec against different attributes, and see which joins are needed
# in what role
my $outer_aliastypes =
$self->_resolve_aliastypes_from_select_args( $from, $outer_select, $where, $outer_attrs );
+ # unroll parents
+ my ($outer_select_chain, $outer_restrict_chain) = map { +{
+ map { $_ => 1 } map { values %$_} map { @$_ } values %{ $outer_aliastypes->{$_} || {} }
+ } } qw/selecting restricting/;
+
# see what's left - throw away if not selecting/restricting
- # also throw in a group_by if restricting to guard against
- # cross-join explosions
- #
+ # also throw in a group_by if a non-selecting multiplier,
+ # to guard against cross-join explosions
+ my $need_outer_group_by;
while (my $j = shift @$from) {
my $alias = $j->[0]{-alias};
- if ($outer_aliastypes->{select}{$alias}) {
- push @outer_from, $j;
+ if (
+ $outer_select_chain->{$alias}
+ ) {
+ push @outer_from, $j
}
- elsif ($outer_aliastypes->{restrict}{$alias}) {
+ elsif ($outer_restrict_chain->{$alias}) {
push @outer_from, $j;
- $outer_attrs->{group_by} ||= $outer_select unless $j->[0]{-is_single};
+ $need_outer_group_by ||= $outer_aliastypes->{multiplying}{$alias} ? 1 : 0;
}
}
# demote the outer_from head
$outer_from[0] = $outer_from[0][0];
+ if ($need_outer_group_by and ! $outer_attrs->{group_by}) {
+
+ my $unprocessed_order_chunks;
+ ($outer_attrs->{group_by}, $unprocessed_order_chunks) = $self->_group_over_selection (
+ \@outer_from, $outer_select, $outer_attrs->{order_by}
+ );
+
+ $self->throw_exception (
+ 'A required group_by clause could not be constructed automatically due to a complex '
+ . 'order_by criteria. Either order_by columns only (no functions) or construct a suitable '
+ . 'group_by by hand'
+ ) if $unprocessed_order_chunks;
+
+ }
+
# 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
return (\@outer_from, $outer_select, $where, $outer_attrs);
}
+#
+# I KNOW THIS SUCKS! GET SQLA2 OUT THE DOOR SO THIS CAN DIE!
+#
# Due to a lack of SQLA2 we fall back to crude scans of all the
# select/where/order/group attributes, in order to determine what
# aliases are neded to fulfill the query. This information is used
# throughout the code to prune unnecessary JOINs from the queries
# in an attempt to reduce the execution time.
# Although the method is pretty horrific, the worst thing that can
-# happen is for it to fail due to an unqualified column, which in
-# turn will result in a vocal exception. Qualifying the column will
-# invariably solve the problem.
+# happen is for it to fail due to some scalar SQL, which in turn will
+# result in a vocal exception.
sub _resolve_aliastypes_from_select_args {
my ( $self, $from, $select, $where, $attrs ) = @_;
or next;
$alias_list->{$al} = $j;
- $aliases_by_type->{multiplying}{$al} = 1
- unless $j->{-is_single};
+ $aliases_by_type->{multiplying}{$al} ||= $j->{-join_path}||[] if (
+ # not array == {from} head == can't be multiplying
+ ( ref($_) eq 'ARRAY' and ! $j->{-is_single} )
+ or
+ # a parent of ours is already a multiplier
+ ( grep { $aliases_by_type->{multiplying}{$_} } @{ $j->{-join_path}||[] } )
+ );
}
+ # get a column to source/alias map (including unqualified ones)
+ my $colinfo = $self->_resolve_column_info ($from);
+
# set up a botched SQLA
my $sql_maker = $self->sql_maker;
- my $sep = quotemeta ($self->_sql_maker_opts->{name_sep} || '.');
- local $sql_maker->{quote_char}; # so that we can regex away
+ # these are throw away results, do not pollute the bind stack
+ local $sql_maker->{select_bind};
+ local $sql_maker->{where_bind};
+ local $sql_maker->{group_bind};
+ local $sql_maker->{having_bind};
+
+ # we can't scan properly without any quoting (\b doesn't cut it
+ # everywhere), so unless there is proper quoting set - use our
+ # own weird impossible character.
+ # Also in the case of no quoting, we need to explicitly disable
+ # name_sep, otherwise sorry nasty legacy syntax like
+ # { 'count(foo.id)' => { '>' => 3 } } will stop working >:(
+ local $sql_maker->{quote_char} = $sql_maker->{quote_char};
+ local $sql_maker->{name_sep} = $sql_maker->{name_sep};
+
+ unless (defined $sql_maker->{quote_char} and length $sql_maker->{quote_char}) {
+ $sql_maker->{quote_char} = ["\x00", "\xFF"];
+ # if we don't unset it we screw up retarded but unfortunately working
+ # 'MAX(foo.bar)' => { '>', 3 }
+ $sql_maker->{name_sep} = '';
+ }
+
+ my ($lquote, $rquote, $sep) = map { quotemeta $_ } ($sql_maker->_quote_chars, $sql_maker->name_sep);
+
+ # generate sql chunks
+ my $to_scan = {
+ restricting => [
+ $sql_maker->_recurse_where ($where),
+ $sql_maker->_parse_rs_attrs ({
+ map { $_ => $attrs->{$_} } (qw/group_by having/)
+ }),
+ ],
+ selecting => [
+ $sql_maker->_recurse_fields ($select),
+ ( map { $_->[0] } $self->_extract_order_criteria ($attrs->{order_by}, $sql_maker) ),
+ ],
+ };
- my $select_sql = $sql_maker->_recurse_fields ($select);
- my $where_sql = $sql_maker->where ($where);
- my $group_by_sql = $sql_maker->_order_by({
- map { $_ => $attrs->{$_} } qw/group_by having/
- });
- my @order_by_chunks = ($self->_parse_order_by ($attrs->{order_by}) );
+ # throw away empty chunks
+ $_ = [ map { $_ || () } @$_ ] for values %$to_scan;
- # match every alias to the sql chunks above
+ # first loop through all fully qualified columns and get the corresponding
+ # alias (should work even if they are in scalarrefs)
for my $alias (keys %$alias_list) {
- my $al_re = qr/\b $alias $sep/x;
-
- for my $piece ($where_sql, $group_by_sql) {
- $aliases_by_type->{restrict}{$alias} = 1 if ($piece =~ $al_re);
+ my $al_re = qr/
+ $lquote $alias $rquote $sep
+ |
+ \b $alias \.
+ /x;
+
+ for my $type (keys %$to_scan) {
+ for my $piece (@{$to_scan->{$type}}) {
+ $aliases_by_type->{$type}{$alias} ||= $alias_list->{$alias}{-join_path}||[]
+ if ($piece =~ $al_re);
+ }
}
+ }
+
+ # now loop through unqualified column names, and try to locate them within
+ # the chunks
+ for my $col (keys %$colinfo) {
+ next if $col =~ / \. /x; # if column is qualified it was caught by the above
+
+ my $col_re = qr/ $lquote $col $rquote /x;
- for my $piece ($select_sql, @order_by_chunks ) {
- $aliases_by_type->{select}{$alias} = 1 if ($piece =~ $al_re);
+ for my $type (keys %$to_scan) {
+ for my $piece (@{$to_scan->{$type}}) {
+ if ($piece =~ $col_re) {
+ my $alias = $colinfo->{$col}{-source_alias};
+ $aliases_by_type->{$type}{$alias} ||= $alias_list->{$alias}{-join_path}||[];
+ }
+ }
}
}
# Add any non-left joins to the restriction list (such joins are indeed restrictions)
for my $j (values %$alias_list) {
my $alias = $j->{-alias} or next;
- $aliases_by_type->{restrict}{$alias} = 1 if (
+ $aliases_by_type->{restricting}{$alias} ||= $j->{-join_path}||[] if (
(not $j->{-join_type})
or
($j->{-join_type} !~ /^left (?: \s+ outer)? $/xi)
);
}
- # mark all join parents as mentioned
- # (e.g. join => { cds => 'tracks' } - tracks will need to bring cds too )
- for my $type (keys %$aliases_by_type) {
- for my $alias (keys %{$aliases_by_type->{$type}}) {
- $aliases_by_type->{$type}{$_} = 1
- for (map { keys %$_ } @{ $alias_list->{$alias}{-join_path} || [] });
+ return $aliases_by_type;
+}
+
+# This is the engine behind { distinct => 1 }
+sub _group_over_selection {
+ my ($self, $from, $select, $order_by) = @_;
+
+ my $rs_column_list = $self->_resolve_column_info ($from);
+
+ my (@group_by, %group_index);
+
+ # the logic is: if it is a { func => val } we assume an aggregate,
+ # otherwise if \'...' or \[...] we assume the user knows what is
+ # going on thus group over it
+ for (@$select) {
+ if (! ref($_) or ref ($_) ne 'HASH' ) {
+ push @group_by, $_;
+ $group_index{$_}++;
+ if ($rs_column_list->{$_} and $_ !~ /\./ ) {
+ # add a fully qualified version as well
+ $group_index{"$rs_column_list->{$_}{-source_alias}.$_"}++;
+ }
}
}
- return $aliases_by_type;
+ # add any order_by parts that are not already present in the group_by
+ # we need to be careful not to add any named functions/aggregates
+ # i.e. order_by => [ ... { count => 'foo' } ... ]
+ my @leftovers;
+ for ($self->_extract_order_criteria($order_by)) {
+ # only consider real columns (for functions the user got to do an explicit group_by)
+ if (@$_ != 1) {
+ push @leftovers, $_;
+ next;
+ }
+ my $chunk = $_->[0];
+ my $colinfo = $rs_column_list->{$chunk} or do {
+ push @leftovers, $_;
+ next;
+ };
+
+ $chunk = "$colinfo->{-source_alias}.$chunk" if $chunk !~ /\./;
+ push @group_by, $chunk unless $group_index{$chunk}++;
+ }
+
+ return wantarray
+ ? (\@group_by, (@leftovers ? \@leftovers : undef) )
+ : \@group_by
+ ;
}
sub _resolve_ident_sources {
# 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") ) {
+ if ( blessed $ident && $ident->isa("DBIx::Class::ResultSource") ) {
# this is compat mode for insert/update/delete which do not deal with aliases
$alias2source->{me} = $ident;
$rs_alias = 'me';
$tabinfo = $_->[0];
}
- $alias2source->{$tabinfo->{-alias}} = $tabinfo->{-source_handle}->resolve
- if ($tabinfo->{-source_handle});
+ $alias2source->{$tabinfo->{-alias}} = $tabinfo->{-rsrc}
+ if ($tabinfo->{-rsrc});
}
}
my ($self, $ident, $colnames) = @_;
my ($alias2src, $root_alias) = $self->_resolve_ident_sources($ident);
- my $sep = $self->_sql_maker_opts->{name_sep} || '.';
- my $qsep = quotemeta $sep;
-
- my (%return, %seen_cols, @auto_colnames);
+ my (%seen_cols, @auto_colnames);
# compile a global list of column names, to be able to properly
# disambiguate unqualified column names (if at all possible)
my $rsrc = $alias2src->{$alias};
for my $colname ($rsrc->columns) {
push @{$seen_cols{$colname}}, $alias;
- push @auto_colnames, "$alias$sep$colname" unless $colnames;
+ push @auto_colnames, "$alias.$colname" unless $colnames;
}
}
grep { @{$seen_cols{$_}} == 1 } (keys %seen_cols),
];
- COLUMN:
+ my (%return, $colinfos);
foreach my $col (@$colnames) {
- my ($alias, $colname) = $col =~ m/^ (?: ([^$qsep]+) $qsep)? (.+) $/x;
+ my ($source_alias, $colname) = $col =~ m/^ (?: ([^\.]+) \. )? (.+) $/x;
- unless ($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;
- }
- }
+ # if the column was seen exactly once - we know which rsrc it came from
+ $source_alias ||= $seen_cols{$colname}[0]
+ if ($seen_cols{$colname} and @{$seen_cols{$colname}} == 1);
- my $rsrc = $alias2src->{$alias};
- $return{$col} = $rsrc && {
- %{$rsrc->column_info($colname)},
+ next unless $source_alias;
+
+ my $rsrc = $alias2src->{$source_alias}
+ or next;
+
+ $return{$col} = {
+ %{
+ ( $colinfos->{$source_alias} ||= $rsrc->columns_info )->{$colname}
+ ||
+ $self->throw_exception(
+ "No such column '$colname' on source " . $rsrc->source_name
+ );
+ },
-result_source => $rsrc,
- -source_alias => $alias,
+ -source_alias => $source_alias,
+ -fq_colname => $col eq $colname ? "$source_alias.$col" : $col,
+ -colname => $colname,
};
+
+ $return{"$source_alias.$colname"} = $return{$col} if $col eq $colname;
}
return \%return;
# the top of the stack, and if not - make sure the chain is inner-joined down
# to the root.
#
-sub _straight_join_to_node {
+sub _inner_join_to_node {
my ($self, $from, $alias) = @_;
# subqueries and other oddness are naturally not supported
# So it looks like we will have to switch some stuff around.
# local() is useless here as we will be leaving the scope
# anyway, and deep cloning is just too fucking expensive
- # So replace the first hashref in the node arrayref manually
+ # So replace the first hashref in the node arrayref manually
my @new_from = ($from->[0]);
- my $sw_idx = { map { values %$_ => 1 } @$switch_branch };
+ my $sw_idx = { map { (values %$_), 1 } @$switch_branch }; #there's one k/v per join-path
for my $j (@{$from}[1 .. $#$from]) {
my $jalias = $j->[0]{-alias};
return \@new_from;
}
-# Most databases do not allow aliasing of tables in UPDATE/DELETE. Thus
-# a condition containing 'me' or other table prefixes will not work
-# at all. What this code tries to do (badly) is introspect the condition
-# and remove all column qualifiers. If it bails out early (returns undef)
-# the calling code should try another approach (e.g. a subquery)
-sub _strip_cond_qualifiers {
- my ($self, $where) = @_;
-
- my $cond = {};
-
- # No-op. No condition, we're updating/deleting everything
- return $cond unless $where;
-
- if (ref $where eq 'ARRAY') {
- $cond = [
- map {
- my %hash;
- foreach my $key (keys %{$_}) {
- $key =~ /([^.]+)$/;
- $hash{$1} = $_->{$key};
- }
- \%hash;
- } @$where
- ];
- }
- elsif (ref $where eq 'HASH') {
- if ( (keys %$where) == 1 && ( (keys %{$where})[0] eq '-and' )) {
- $cond->{-and} = [];
- my @cond = @{$where->{-and}};
- for (my $i = 0; $i < @cond; $i++) {
- my $entry = $cond[$i];
- my $hash;
- my $ref = ref $entry;
- if ($ref eq 'HASH' or $ref eq 'ARRAY') {
- $hash = $self->_strip_cond_qualifiers($entry);
- }
- elsif (! $ref) {
- $entry =~ /([^.]+)$/;
- $hash->{$1} = $cond[++$i];
+# yet another atrocity: attempt to extract all columns from a
+# where condition by hooking _quote
+sub _extract_condition_columns {
+ my ($self, $cond, $sql_maker) = @_;
+
+ return [] unless $cond;
+
+ $sql_maker ||= $self->{_sql_ident_capturer} ||= do {
+ # FIXME - replace with a Moo trait
+ my $orig_sm_class = ref $self->sql_maker;
+ my $smic_class = "${orig_sm_class}::_IdentCapture_";
+
+ unless ($smic_class->isa('SQL::Abstract')) {
+
+ no strict 'refs';
+ *{"${smic_class}::_quote"} = subname "${smic_class}::_quote" => sub {
+ my ($self, $ident) = @_;
+ if (ref $ident eq 'SCALAR') {
+ $ident = $$ident;
+ my $storage_quotes = $self->sql_quote_char || '"';
+ my ($ql, $qr) = map
+ { quotemeta $_ }
+ (ref $storage_quotes eq 'ARRAY' ? @$storage_quotes : ($storage_quotes) x 2 )
+ ;
+
+ while ($ident =~ /
+ $ql (\w+) $qr
+ |
+ ([\w\.]+)
+ /xg) {
+ $self->{_captured_idents}{$1||$2}++;
+ }
}
else {
- $self->throw_exception ("_strip_cond_qualifiers() is unable to handle a condition reftype $ref");
+ $self->{_captured_idents}{$ident}++;
}
- push @{$cond->{-and}}, $hash;
- }
+ return $ident;
+ };
+
+ *{"${smic_class}::_get_captured_idents"} = subname "${smic_class}::_get_captures" => sub {
+ (delete shift->{_captured_idents}) || {};
+ };
+
+ $self->inject_base ($smic_class, $orig_sm_class);
+
}
- else {
- foreach my $key (keys %$where) {
- $key =~ /([^.]+)$/;
- $cond->{$1} = $where->{$key};
- }
+
+ $smic_class->new();
+ };
+
+ $sql_maker->_recurse_where($cond);
+
+ return [ sort keys %{$sql_maker->_get_captured_idents} ];
+}
+
+sub _extract_order_criteria {
+ my ($self, $order_by, $sql_maker) = @_;
+
+ my $parser = sub {
+ my ($sql_maker, $order_by) = @_;
+
+ return scalar $sql_maker->_order_by_chunks ($order_by)
+ unless wantarray;
+
+ my @chunks;
+ for ($sql_maker->_order_by_chunks ($order_by) ) {
+ my $chunk = ref $_ ? $_ : [ $_ ];
+ $chunk->[0] =~ s/\s+ (?: ASC|DESC ) \s* $//ix;
+ push @chunks, $chunk;
}
+
+ return @chunks;
+ };
+
+ if ($sql_maker) {
+ return $parser->($sql_maker, $order_by);
}
else {
- return undef;
+ $sql_maker = $self->sql_maker;
+ local $sql_maker->{quote_char};
+ return $parser->($sql_maker, $order_by);
}
-
- return $cond;
}
-sub _parse_order_by {
- my ($self, $order_by) = @_;
+sub _order_by_is_stable {
+ my ($self, $ident, $order_by, $where) = @_;
- return scalar $self->sql_maker->_order_by_chunks ($order_by)
- unless wantarray;
+ my $colinfo = $self->_resolve_column_info($ident, [
+ (map { $_->[0] } $self->_extract_order_criteria($order_by)),
+ $where ? @{$self->_extract_fixed_condition_columns($where)} :(),
+ ]);
- my $sql_maker = $self->sql_maker;
- local $sql_maker->{quote_char}; #disable quoting
- my @chunks;
- for my $chunk (map { ref $_ ? @$_ : $_ } ($sql_maker->_order_by_chunks ($order_by) ) ) {
- $chunk =~ s/\s+ (?: ASC|DESC ) \s* $//ix;
- push @chunks, $chunk;
+ return undef unless keys %$colinfo;
+
+ my $cols_per_src;
+ $cols_per_src->{$_->{-source_alias}}{$_->{-colname}} = $_ for values %$colinfo;
+
+ for (values %$cols_per_src) {
+ my $src = (values %$_)[0]->{-result_source};
+ return 1 if $src->_identifying_column_set($_);
}
- return @chunks;
+ return undef;
+}
+
+# returns an arrayref of column names which *definitely* have som
+# sort of non-nullable equality requested in the given condition
+# specification. This is used to figure out if a resultset is
+# constrained to a column which is part of a unique constraint,
+# which in turn allows us to better predict how ordering will behave
+# etc.
+#
+# this is a rudimentary, incomplete, and error-prone extractor
+# however this is OK - it is conservative, and if we can not find
+# something that is in fact there - the stack will recover gracefully
+# Also - DQ and the mst it rode in on will save us all RSN!!!
+sub _extract_fixed_condition_columns {
+ my ($self, $where, $nested) = @_;
+
+ return unless ref $where eq 'HASH';
+
+ my @cols;
+ for my $lhs (keys %$where) {
+ if ($lhs =~ /^\-and$/i) {
+ push @cols, ref $where->{$lhs} eq 'ARRAY'
+ ? ( map { $self->_extract_fixed_condition_columns($_, 1) } @{$where->{$lhs}} )
+ : $self->_extract_fixed_condition_columns($where->{$lhs}, 1)
+ ;
+ }
+ elsif ($lhs !~ /^\-/) {
+ my $val = $where->{$lhs};
+
+ push @cols, $lhs if (defined $val and (
+ ! ref $val
+ or
+ (ref $val eq 'HASH' and keys %$val == 1 and defined $val->{'='})
+ ));
+ }
+ }
+ return $nested ? @cols : \@cols;
}
1;
projects / dbsrgits/DBIx-Class.git / blobdiff