package # Hide from PAUSE
DBIx::Class::SQLAHacks;
-# This module is a subclass of SQL::Abstract::Limit and includes a number
-# of DBIC-specific workarounds, not yet suitable for inclusion into the
-# SQLA core
-
-use base qw/SQL::Abstract::Limit/;
+# This module is a subclass of SQL::Abstract and includes a number of
+# DBIC-specific workarounds, not yet suitable for inclusion into the
+# SQLA core.
+# It also provides all (and more than) the functionality of
+# SQL::Abstract::Limit, which proved to be very hard to keep updated
+
+use base qw/
+ DBIx::Class::SQLAHacks::LimitDialects
+ SQL::Abstract
+ Class::Accessor::Grouped
+/;
+use mro 'c3';
use strict;
use warnings;
-use Carp::Clan qw/^DBIx::Class|^SQL::Abstract/;
-use Sub::Name();
+use Sub::Name 'subname';
+use Carp::Clan qw/^DBIx::Class|^SQL::Abstract|^Try::Tiny/;
+use namespace::clean;
+
+__PACKAGE__->mk_group_accessors (simple => qw/quote_char name_sep limit_dialect/);
BEGIN {
# reinstall the carp()/croak() functions imported into SQL::Abstract
for my $f (qw/carp croak/) {
my $orig = \&{"SQL::Abstract::$f"};
- *{"SQL::Abstract::$f"} = Sub::Name::subname "SQL::Abstract::$f" =>
+ my $clan_import = \&{$f};
+ *{"SQL::Abstract::$f"} = subname "SQL::Abstract::$f" =>
sub {
if (Carp::longmess() =~ /DBIx::Class::SQLAHacks::[\w]+ .+? called \s at/x) {
- __PACKAGE__->can($f)->(@_);
+ $clan_import->(@_);
}
else {
goto $orig;
}
}
+# the "oh noes offset/top without limit" constant
+# limited to 32 bits for sanity (and consistency,
+# since it is ultimately handed to sprintf %u)
+# Implemented as a method, since ::Storage::DBI also
+# refers to it (i.e. for the case of software_limit or
+# as the value to abuse with MSSQL ordered subqueries)
+sub __max_int { 0xFFFFFFFF };
-# Tries to determine limit dialect.
-#
-sub new {
- my $self = shift->SUPER::new(@_);
-
- # This prevents the caching of $dbh in S::A::L, I believe
- # If limit_dialect is a ref (like a $dbh), go ahead and replace
- # it with what it resolves to:
- $self->{limit_dialect} = $self->_find_syntax($self->{limit_dialect})
- if ref $self->{limit_dialect};
-
- $self;
-}
-
-
-# ANSI standard Limit/Offset implementation. DB2 and MSSQL use this
-sub _RowNumberOver {
- my ($self, $sql, $order, $rows, $offset ) = @_;
-
- # get the select to make the final amount of columns equal the original one
- my ($select) = $sql =~ /^ \s* SELECT \s+ (.+?) \s+ FROM/ix
- or croak "Unrecognizable SELECT: $sql";
-
- # get the order_by only (or make up an order if none exists)
- my $order_by = $self->_order_by(
- (delete $order->{order_by}) || $self->_rno_default_order
- );
-
- # whatever is left of the order_by
- my $group_having = $self->_order_by($order);
-
- my $qalias = $self->_quote ($self->{_dbic_rs_attrs}{alias});
-
- $sql = sprintf (<<EOS, $offset + 1, $offset + $rows, );
-
-SELECT $select FROM (
- SELECT $qalias.*, ROW_NUMBER() OVER($order_by ) AS rno__row__index FROM (
- ${sql}${group_having}
- ) $qalias
-) $qalias WHERE rno__row__index BETWEEN %d AND %d
-
-EOS
-
- $sql =~ s/\s*\n\s*/ /g; # easier to read in the debugger
- return $sql;
-}
-
-# some databases are happy with OVER (), some need OVER (ORDER BY (SELECT (1)) )
-sub _rno_default_order {
- return undef;
-}
-
-# Informix specific limit, almost like LIMIT/OFFSET
-sub _SkipFirst {
- my ($self, $sql, $order, $rows, $offset) = @_;
-
- $sql =~ s/^ \s* SELECT \s+ //ix
- or croak "Unrecognizable SELECT: $sql";
-
- return sprintf ('SELECT %s%s%s%s',
- $offset
- ? sprintf ('SKIP %d ', $offset)
- : ''
- ,
- sprintf ('FIRST %d ', $rows),
- $sql,
- $self->_order_by ($order),
- );
-}
-
-# Firebird specific limit, reverse of _SkipFirst for Informix
-sub _FirstSkip {
- my ($self, $sql, $order, $rows, $offset) = @_;
-
- $sql =~ s/^ \s* SELECT \s+ //ix
- or croak "Unrecognizable SELECT: $sql";
-
- return sprintf ('SELECT %s%s%s%s',
- sprintf ('FIRST %d ', $rows),
- $offset
- ? sprintf ('SKIP %d ', $offset)
- : ''
- ,
- $sql,
- $self->_order_by ($order),
- );
-}
-
-# Crappy Top based Limit/Offset support. Legacy from MSSQL.
-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 || '.';
- my $esc_name_sep = "\Q$name_sep\E";
- my $col_re = qr/ ^ (?: (.+) $esc_name_sep )? ([^$esc_name_sep]+) $ /x;
-
- my $rs_alias = $self->{_dbic_rs_attrs}{alias};
- my $quoted_rs_alias = $self->_quote ($rs_alias);
-
- # 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} && $seen_names{$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 $req_order = $order->{order_by};
-
- # examine normalized version, collapses nesting
- my $limit_order;
- if (scalar $self->_order_by_chunks ($req_order)) {
- $limit_order = $req_order;
- }
- else {
- $limit_order = [ map
- { join ('', $rs_alias, $name_sep, $_ ) }
- ( $self->{_dbic_rs_attrs}{_source_handle}->resolve->primary_columns )
- ];
- }
-
- my ( $order_by_inner, $order_by_outer ) = $self->_order_directions($limit_order);
- my $order_by_requested = $self->_order_by ($req_order);
+# Handle limit-dialect selection
+sub select {
+ my ($self, $table, $fields, $where, $rs_attrs, $limit, $offset) = @_;
- # generate the rest
- delete $order->{order_by};
- my $grpby_having = $self->_order_by ($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";
- }
+ $fields = $self->_recurse_fields($fields);
- # 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;
+ if (defined $offset) {
+ croak ('A supplied offset must be a non-negative integer')
+ if ( $offset =~ /\D/ or $offset < 0 );
}
+ $offset ||= 0;
-
- 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
- (
- $sql
- ) $quoted_rs_alias
- $order_by_outer
-SQL
-
+ if (defined $limit) {
+ croak ('A supplied limit must be a positive integer')
+ if ( $limit =~ /\D/ or $limit <= 0 );
}
-
- if ($order_by_requested) {
- $sql = <<"SQL";
-
- SELECT $outer_select FROM
- ( $sql ) $quoted_rs_alias
- $order_by_requested
-SQL
-
+ elsif ($offset) {
+ $limit = $self->__max_int;
}
- $sql =~ s/\s*\n\s*/ /g; # parsing out multiline statements is harder than a single line
- return $sql;
-}
-# action at a distance to shorten Top code above
-sub __record_alias {
- my ($self, $register, $alias, $fqcol, $col) = @_;
+ my ($sql, @bind);
+ if ($limit) {
+ # this is legacy code-flow from SQLA::Limit, it is not set in stone
- # record qualified name
- $register->{$fqcol} = $alias;
- $register->{$self->_quote($fqcol)} = $alias;
+ ($sql, @bind) = $self->next::method ($table, $fields, $where);
- return unless $col;
+ my $limiter =
+ $self->can ('emulate_limit') # also backcompat hook from SQLA::Limit
+ ||
+ do {
+ my $dialect = $self->limit_dialect
+ or croak "Unable to generate SQL-limit - no limit dialect specified on $self, and no emulate_limit method found";
+ $self->can ("_$dialect")
+ or croak "SQLAHacks does not implement the requested dialect '$dialect'";
+ }
+ ;
- # record unqualified name, undef (no adjustment) if a duplicate is found
- if (exists $register->{$col}) {
- $register->{$col} = undef;
+ $sql = $self->$limiter ($sql, $rs_attrs, $limit, $offset);
}
else {
- $register->{$col} = $alias;
+ ($sql, @bind) = $self->next::method ($table, $fields, $where, $rs_attrs);
}
- $register->{$self->_quote($col)} = $register->{$col};
-}
-
+ push @{$self->{where_bind}}, @bind;
+# this *must* be called, otherwise extra binds will remain in the sql-maker
+ my @all_bind = $self->_assemble_binds;
-# While we're at it, this should make LIMIT queries more efficient,
-# without digging into things too deeply
-sub _find_syntax {
- my ($self, $syntax) = @_;
- return $self->{_cached_syntax} ||= $self->SUPER::_find_syntax($syntax);
+ return wantarray ? ($sql, @all_bind) : $sql;
}
-my $for_syntax = {
- update => 'FOR UPDATE',
- shared => 'FOR SHARE',
-};
-# Quotes table names, handles "limit" dialects (e.g. where rownum between x and
-# y), supports SELECT ... FOR UPDATE and SELECT ... FOR SHARE.
-sub select {
- my ($self, $table, $fields, $where, $order, @rest) = @_;
-
- $self->{"${_}_bind"} = [] for (qw/having from order/);
-
- if (not ref($table) or ref($table) eq 'SCALAR') {
- $table = $self->_quote($table);
- }
-
- local $self->{rownum_hack_count} = 1
- if (defined $rest[0] && $self->{limit_dialect} eq 'RowNum');
- @rest = (-1) unless defined $rest[0];
- croak "LIMIT 0 Does Not Compute" if $rest[0] == 0;
- # and anyway, SQL::Abstract::Limit will cause a barf if we don't first
- my ($sql, @where_bind) = $self->SUPER::select(
- $table, $self->_recurse_fields($fields), $where, $order, @rest
- );
- 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;
+sub _assemble_binds {
+ my $self = shift;
+ return map { @{ (delete $self->{"${_}_bind"}) || [] } } (qw/from where having order/);
}
-# Quotes table names, and handles default inserts
+# Handle default inserts
sub insert {
- my $self = shift;
- my $table = shift;
- $table = $self->_quote($table);
+# optimized due to hotttnesss
+# my ($self, $table, $data, $options) = @_;
# 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]} ) ) {
- my $sql = "INSERT INTO ${table} DEFAULT VALUES";
+ if (! $_[2] or (ref $_[2] eq 'HASH' and !keys %{$_[2]} ) ) {
+ my $sql = "INSERT INTO $_[1] DEFAULT VALUES";
- if (my @returning = @{ ($_[1]||{})->{returning} || [] }) {
- $sql .= ' RETURNING (' . (join ', ' => map $self->_quote($_), @returning)
- . ')';
+ if (my $ret = ($_[3]||{})->{returning} ) {
+ $sql .= $_[0]->_insert_returning ($ret);
}
return $sql;
}
- $self->SUPER::insert($table, @_);
-}
-
-# Just quotes table names.
-sub update {
- my $self = shift;
- my $table = shift;
- $table = $self->_quote($table);
- $self->SUPER::update($table, @_);
-}
-
-# Just quotes table names.
-sub delete {
- my $self = shift;
- my $table = shift;
- $table = $self->_quote($table);
- $self->SUPER::delete($table, @_);
-}
-
-sub _emulate_limit {
- my $self = shift;
- if ($_[3] == -1) {
- return $_[1].$self->_order_by($_[2]);
- } else {
- return $self->SUPER::_emulate_limit(@_);
- }
+ next::method(@_);
}
sub _recurse_fields {
- my ($self, $fields, $params) = @_;
+ my ($self, $fields) = @_;
my $ref = ref $fields;
return $self->_quote($fields) unless $ref;
return $$fields if $ref eq 'SCALAR';
if ($ref eq 'ARRAY') {
- return join(', ', map {
- $self->_recurse_fields($_)
- .(exists $self->{rownum_hack_count} && !($params && $params->{no_rownum_hack})
- ? ' AS col'.$self->{rownum_hack_count}++
- : '')
- } @$fields);
+ return join(', ', map { $self->_recurse_fields($_) } @$fields);
}
elsif ($ref eq 'HASH') {
- my %hash = %$fields;
+ my %hash = %$fields; # shallow copy
my $as = delete $hash{-as}; # if supplied
- my ($func, $args) = each %hash;
- delete $hash{$func};
+ my ($func, $args, @toomany) = %hash;
+
+ # there should be only one pair
+ if (@toomany) {
+ croak "Malformed select argument - too many keys in hash: " . join (',', keys %$fields );
+ }
if (lc ($func) eq 'distinct' && ref $args eq 'ARRAY' && @$args > 1) {
croak (
: ''
);
- # there should be nothing left
- if (keys %hash) {
- croak "Malformed select argument - too many keys in hash: " . join (',', keys %$fields );
- }
-
return $select;
}
# Is the second check absolutely necessary?
}
}
-sub _order_by {
+my $for_syntax = {
+ update => 'FOR UPDATE',
+ shared => 'FOR SHARE',
+};
+
+# this used to be a part of _order_by but is broken out for clarity.
+# What we have been doing forever is hijacking the $order arg of
+# SQLA::select to pass in arbitrary pieces of data (first the group_by,
+# then pretty much the entire resultset attr-hash, as more and more
+# things in the SQLA space need to have mopre info about the $rs they
+# create SQL for. The alternative would be to keep expanding the
+# signature of _select with more and more positional parameters, which
+# is just gross. All hail SQLA2!
+sub _parse_rs_attrs {
my ($self, $arg) = @_;
- if (ref $arg eq 'HASH' and keys %$arg and not grep { $_ =~ /^-(?:desc|asc)/i } keys %$arg ) {
+ my $sql = '';
- my $ret = '';
+ if (my $g = $self->_recurse_fields($arg->{group_by}) ) {
+ $sql .= $self->_sqlcase(' group by ') . $g;
+ }
- if (my $g = $self->_recurse_fields($arg->{group_by}, { no_rownum_hack => 1 }) ) {
- $ret = $self->_sqlcase(' group by ') . $g;
- }
+ if (defined $arg->{having}) {
+ my ($frag, @bind) = $self->_recurse_where($arg->{having});
+ push(@{$self->{having_bind}}, @bind);
+ $sql .= $self->_sqlcase(' having ') . $frag;
+ }
- if (defined $arg->{having}) {
- my ($frag, @bind) = $self->_recurse_where($arg->{having});
- push(@{$self->{having_bind}}, @bind);
- $ret .= $self->_sqlcase(' having ').$frag;
- }
+ if (defined $arg->{order_by}) {
+ $sql .= $self->_order_by ($arg->{order_by});
+ }
- if (defined $arg->{order_by}) {
- my ($frag, @bind) = $self->SUPER::_order_by($arg->{order_by});
- push(@{$self->{order_bind}}, @bind);
- $ret .= $frag;
- }
+ if (my $for = $arg->{for}) {
+ $sql .= " $for_syntax->{$for}" if $for_syntax->{$for};
+ }
+
+ return $sql;
+}
- return $ret;
+sub _order_by {
+ my ($self, $arg) = @_;
+
+ # check that we are not called in legacy mode (order_by as 4th argument)
+ if (ref $arg eq 'HASH' and not grep { $_ =~ /^-(?:desc|asc)/i } keys %$arg ) {
+ return $self->_parse_rs_attrs ($arg);
}
else {
- my ($sql, @bind) = $self->SUPER::_order_by ($arg);
- push(@{$self->{order_bind}}, @bind);
+ my ($sql, @bind) = $self->next::method($arg);
+ push @{$self->{order_bind}}, @bind;
return $sql;
}
}
-sub _order_directions {
- my ($self, $order) = @_;
+sub _table {
+# optimized due to hotttnesss
+# my ($self, $from) = @_;
+ if (my $ref = ref $_[1] ) {
+ if ($ref eq 'ARRAY') {
+ return $_[0]->_recurse_from(@{$_[1]});
+ }
+ elsif ($ref eq 'HASH') {
+ return $_[0]->_make_as($_[1]);
+ }
+ }
- # strip bind values - none of the current _order_directions users support them
- return $self->SUPER::_order_directions( [ map
- { ref $_ ? $_->[0] : $_ }
- $self->_order_by_chunks ($order)
- ]);
+ return $_[0]->next::method ($_[1]);
}
-sub _table {
- my ($self, $from) = @_;
- if (ref $from eq 'ARRAY') {
- return $self->_recurse_from(@$from);
- } elsif (ref $from eq 'HASH') {
- return $self->_make_as($from);
- } else {
- return $from; # would love to quote here but _table ends up getting called
- # twice during an ->select without a limit clause due to
- # the way S::A::Limit->select works. should maybe consider
- # bypassing this and doing S::A::select($self, ...) in
- # our select method above. meantime, quoting shims have
- # been added to select/insert/update/delete here
- }
+sub _generate_join_clause {
+ my ($self, $join_type) = @_;
+
+ return sprintf ('%s JOIN ',
+ $join_type ? ' ' . uc($join_type) : ''
+ );
}
sub _recurse_from {
$join_type = $self->{_default_jointype} if not defined $join_type;
- my $join_clause = sprintf ('%s JOIN ',
- $join_type ? ' ' . uc($join_type) : ''
- );
- push @sqlf, $join_clause;
+ push @sqlf, $self->_generate_join_clause( $join_type );
if (ref $to eq 'ARRAY') {
push(@sqlf, '(', $self->_recurse_from(@$to), ')');
} elsif (ref $cond eq 'ARRAY') {
return join(' OR ', map { $self->_join_condition($_) } @$cond);
} else {
- die "Can't handle this yet!";
+ croak "Can't handle this yet!";
}
}
-sub _quote {
- my ($self, $label) = @_;
- return '' unless defined $label;
- return $$label if ref($label) eq 'SCALAR';
- return "*" if $label eq '*';
- return $label unless $self->{quote_char};
- if(ref $self->{quote_char} eq "ARRAY"){
- return $self->{quote_char}->[0] . $label . $self->{quote_char}->[1]
- if !defined $self->{name_sep};
- my $sep = $self->{name_sep};
- return join($self->{name_sep},
- map { $self->{quote_char}->[0] . $_ . $self->{quote_char}->[1] }
- split(/\Q$sep\E/,$label));
- }
- return $self->SUPER::_quote($label);
-}
-
-sub limit_dialect {
- my $self = shift;
- $self->{limit_dialect} = shift if @_;
- return $self->{limit_dialect};
-}
-
-# Set to an array-ref to specify separate left and right quotes for table names.
-# A single scalar is equivalen to [ $char, $char ]
-sub quote_char {
- my $self = shift;
- $self->{quote_char} = shift if @_;
- return $self->{quote_char};
-}
-
-# Character separating quoted table names.
-sub name_sep {
- my $self = shift;
- $self->{name_sep} = shift if @_;
- return $self->{name_sep};
-}
-
1;