sub _Top {
my ( $self, $sql, $order, $rows, $offset ) = @_;
+ # mangle the input sql so it can be properly aliased in the outer queries
+ $sql =~ s/^ \s* SELECT \s+ (.+?) \s+ (?=FROM)//ix
+ or croak "Unrecognizable SELECT: $sql";
+ my $sql_select = $1;
+ my @sql_select = split (/\s*,\s*/, $sql_select);
+
+ # we can't support subqueries (in fact MSSQL can't) - croak
+ if (@sql_select != @{$self->{_dbic_rs_attrs}{select}}) {
+ croak (sprintf (
+ 'SQL SELECT did not parse cleanly - retrieved %d comma separated elements, while '
+ . 'the resultset select attribure contains %d elements: %s',
+ scalar @sql_select,
+ scalar @{$self->{_dbic_rs_attrs}{select}},
+ $sql_select,
+ ));
+ }
+
+ my $name_sep = $self->name_sep || '.';
+ $name_sep = "\Q$name_sep\E";
+ my $col_re = qr/ ^ (?: (.+) $name_sep )? ([^$name_sep]+) $ /x;
+
+ # construct the new select lists, rename(alias) some columns if necessary
+ my (@outer_select, @inner_select, %seen_names, %col_aliases, %outer_col_aliases);
+
+ for (@{$self->{_dbic_rs_attrs}{select}}) {
+ next if ref $_;
+ my ($table, $orig_colname) = ( $_ =~ $col_re );
+ next unless $table;
+ $seen_names{$orig_colname}++;
+ }
+
+ for my $i (0 .. $#sql_select) {
+
+ my $colsel_arg = $self->{_dbic_rs_attrs}{select}[$i];
+ my $colsel_sql = $sql_select[$i];
+
+ # this may or may not work (in case of a scalarref or something)
+ my ($table, $orig_colname) = ( $colsel_arg =~ $col_re );
+
+ my $quoted_alias;
+ # do not attempt to understand non-scalar selects - alias numerically
+ if (ref $colsel_arg) {
+ $quoted_alias = $self->_quote ('column_' . (@inner_select + 1) );
+ }
+ # column name seen more than once - alias it
+ elsif ($orig_colname && ($seen_names{$orig_colname} > 1) ) {
+ $quoted_alias = $self->_quote ("${table}__${orig_colname}");
+ }
+
+ # we did rename - make a record and adjust
+ if ($quoted_alias) {
+ # alias inner
+ push @inner_select, "$colsel_sql AS $quoted_alias";
+
+ # push alias to outer
+ push @outer_select, $quoted_alias;
+
+ # Any aliasing accumulated here will be considered
+ # both for inner and outer adjustments of ORDER BY
+ $self->__record_alias (
+ \%col_aliases,
+ $quoted_alias,
+ $colsel_arg,
+ $table ? $orig_colname : undef,
+ );
+ }
+
+ # otherwise just leave things intact inside, and use the abbreviated one outside
+ # (as we do not have table names anymore)
+ else {
+ push @inner_select, $colsel_sql;
+
+ my $outer_quoted = $self->_quote ($orig_colname); # it was not a duplicate so should just work
+ push @outer_select, $outer_quoted;
+ $self->__record_alias (
+ \%outer_col_aliases,
+ $outer_quoted,
+ $colsel_arg,
+ $table ? $orig_colname : undef,
+ );
+ }
+ }
+
+ my $outer_select = join (', ', @outer_select );
+ my $inner_select = join (', ', @inner_select );
+
+ %outer_col_aliases = (%outer_col_aliases, %col_aliases);
+
+ # deal with order
croak '$order supplied to SQLAHacks limit emulators must be a hash'
if (ref $order ne 'HASH');
$order = { %$order }; #copy
- my $last = $rows + $offset;
-
- my $req_order = $self->_order_by ($order->{order_by});
+ my $req_order = [ $self->_order_by_chunks ($order->{order_by}) ];
+ my $limit_order = [ @$req_order ? @$req_order : $self->_order_by_chunks ($order->{_virtual_order_by}) ];
- my $limit_order = $req_order ? $order->{order_by} : $order->{_virtual_order_by};
+ my ( $order_by_inner, $order_by_outer ) = $self->_order_directions($limit_order);
+ my $order_by_requested = $self->_order_by ($req_order);
+ # generate the rest
delete $order->{$_} for qw/order_by _virtual_order_by/;
my $grpby_having = $self->_order_by ($order);
- my ( $order_by_inner, $order_by_outer ) = $self->_order_directions($limit_order);
+ # short circuit for counts - the ordering complexity is needless
+ if ($self->{_dbic_rs_attrs}{-for_count_only}) {
+ return "SELECT TOP $rows $inner_select $sql $grpby_having $order_by_outer";
+ }
- $sql =~ s/^\s*(SELECT|select)//;
- $sql = <<"SQL";
- SELECT * FROM
- (
- SELECT TOP $rows * FROM
+ # we can't really adjust the order_by columns, as introspection is lacking
+ # resort to simple substitution
+ for my $col (keys %outer_col_aliases) {
+ for ($order_by_requested, $order_by_outer) {
+ $_ =~ s/\s+$col\s+/ $outer_col_aliases{$col} /g;
+ }
+ }
+ for my $col (keys %col_aliases) {
+ $order_by_inner =~ s/\s+$col\s+/$col_aliases{$col}/g;
+ }
+
+ my $inner_lim = $rows + $offset;
+
+ $sql = "SELECT TOP $inner_lim $inner_select $sql $grpby_having $order_by_inner";
+
+ if ($offset) {
+ $sql = <<"SQL";
+
+ SELECT TOP $rows $outer_select FROM
(
- SELECT TOP $last $sql $grpby_having $order_by_inner
- ) AS foo
+ $sql
+ ) AS inner_sel
$order_by_outer
- ) AS bar
- $req_order
+SQL
+
+ }
+ if ($order_by_requested) {
+ $sql = <<"SQL";
+
+ SELECT $outer_select FROM
+ ( $sql ) AS outer_sel
+ $order_by_requested;
SQL
- return $sql;
+
+ }
+
+ return $sql;
+}
+
+# action at a distance to shorten Top code above
+sub __record_alias {
+ my ($self, $register, $alias, $fqcol, $col) = @_;
+
+ # record qualified name
+ $register->{$fqcol} = $alias;
+ $register->{$self->_quote($fqcol)} = $alias;
+
+ return unless $col;
+
+ # record unqialified name, undef (no adjustment) if a duplicate is found
+ if (exists $register->{$col}) {
+ $register->{$col} = undef;
+ }
+ else {
+ $register->{$col} = $alias;
+ }
+
+ $register->{$self->_quote($col)} = $register->{$col};
}
return $self->{_cached_syntax} ||= $self->SUPER::_find_syntax($syntax);
}
+my $for_syntax = {
+ update => 'FOR UPDATE',
+ shared => 'FOR SHARE',
+};
sub select {
my ($self, $table, $fields, $where, $order, @rest) = @_;
my ($sql, @where_bind) = $self->SUPER::select(
$table, $self->_recurse_fields($fields), $where, $order, @rest
);
- $sql .=
- $self->{for} ?
- (
- $self->{for} eq 'update' ? ' FOR UPDATE' :
- $self->{for} eq 'shared' ? ' FOR SHARE' :
- ''
- ) :
- ''
- ;
+ if (my $for = delete $self->{_dbic_rs_attrs}{for}) {
+ $sql .= " $for_syntax->{$for}" if $for_syntax->{$for};
+ }
+
return wantarray ? ($sql, @{$self->{from_bind}}, @where_bind, @{$self->{having_bind}}, @{$self->{order_bind}} ) : $sql;
}
my $self = shift;
my $table = shift;
$table = $self->_quote($table) unless ref($table);
+
+ # SQLA will emit INSERT INTO $table ( ) VALUES ( )
+ # which is sadly understood only by MySQL. Change default behavior here,
+ # until SQLA2 comes with proper dialect support
+ if (! $_[0] or (ref $_[0] eq 'HASH' and !keys %{$_[0]} ) ) {
+ return "INSERT INTO ${table} DEFAULT VALUES"
+ }
+
$self->SUPER::insert($table, @_);
}
projects / dbsrgits/DBIx-Class.git / blobdiff