From 3bc6ea42732020b00fef53a9b556e4a37e591bd7 Mon Sep 17 00:00:00 2001 From: "mkanat%bugzilla.org" <> Date: Sat, 10 Mar 2007 04:13:09 +0000 Subject: Bug 347439: Implement support for referential integrity in Bugzilla::DB::Schema and implement it on profiles_activity Patch By Max Kanat-Alexander (module owner) a=mkanat --- Bugzilla/DB.pm | 5 +- Bugzilla/DB/Schema.pm | 245 +++++++++++++++++++++++++++++++++++++++----- Bugzilla/DB/Schema/Mysql.pm | 29 ++++++ Bugzilla/Install/DB.pm | 47 +++++++++ 4 files changed, 297 insertions(+), 29 deletions(-) diff --git a/Bugzilla/DB.pm b/Bugzilla/DB.pm index 9f517a8e7..e4e30a8d3 100644 --- a/Bugzilla/DB.pm +++ b/Bugzilla/DB.pm @@ -515,10 +515,11 @@ sub bz_alter_column_raw { my @statements = $self->_bz_real_schema->get_alter_column_ddl( $table, $name, $new_def, defined $set_nulls_to ? $self->quote($set_nulls_to) : undef); - my $new_ddl = $self->_bz_schema->get_type_ddl($new_def); + my $new_ddl = $self->_bz_schema->get_display_ddl($table, $name, $new_def); print "Updating column $name in table $table ...\n"; if (defined $current_def) { - my $old_ddl = $self->_bz_schema->get_type_ddl($current_def); + my $old_ddl = $self->_bz_schema->get_display_ddl($table, $name, + $current_def); print "Old: $old_ddl\n"; } print "New: $new_ddl\n"; diff --git a/Bugzilla/DB/Schema.pm b/Bugzilla/DB/Schema.pm index 661677319..a97d3428b 100644 --- a/Bugzilla/DB/Schema.pm +++ b/Bugzilla/DB/Schema.pm @@ -96,7 +96,21 @@ more about how this integrates into the rest of Bugzilla. =head1 CONSTANTS -=over 4 +=over + +=item C + +Because of L, certain tables must be created +before other tables. L can't specify this, because +it's a hash. So we specify it here. When calling C, +these tables will be returned before the other tables. + +=cut + +use constant TABLES_FIRST => qw( + fielddefs + profiles +); =item C @@ -157,6 +171,49 @@ which can be used to specify the type of index such as UNIQUE or FULLTEXT. =back +=head2 Referential Integrity + +Bugzilla::DB::Schema supports "foreign keys", a way of saying +that "Column X may only contain values from Column Y in Table Z". +For example, in Bugzilla, bugs.resolution should only contain +values from the resolution.values field. + +It does this by adding an additional item to a column, called C. +This is a hash with the following members: + +=over + +=item C + +The table the foreign key points at + +=item C + +The column pointed at in that table. + +=item C + +What to do if the row in the parent table is deleted. Choices are +C or C. + +C means the deletion of the row in the parent table will +be forbidden by the database if there is a row in I table that +still refers to it. This is the default, if you don't specify +C. + +C means that this row will be deleted along with that row. + +=item C + +What to do if the value in the parent table is updated. It has the +same choices as L, except it defaults to C, which means +"also update this column in this table." + +=back + +Note that not all our supported databases actually enforce C +and C, so don't depend on them. + =cut use constant SCHEMA_VERSION => '2.00'; @@ -645,10 +702,17 @@ use constant ABSTRACT_SCHEMA => { profiles_activity => { FIELDS => [ - userid => {TYPE => 'INT3', NOTNULL => 1}, - who => {TYPE => 'INT3', NOTNULL => 1}, + userid => {TYPE => 'INT3', NOTNULL => 1, + REFERENCES => {TABLE => 'profiles', + COLUMN => 'userid', + DELETE => 'CASCADE'}}, + who => {TYPE => 'INT3', NOTNULL => 1, + REFERENCES => {TABLE => 'profiles', + COLUMN => 'userid'}}, profiles_when => {TYPE => 'DATETIME', NOTNULL => 1}, - fieldid => {TYPE => 'INT3', NOTNULL => 1}, + fieldid => {TYPE => 'INT3', NOTNULL => 1, + REFERENCES => {TABLE => 'fielddefs', + COLUMN => 'id'}}, oldvalue => {TYPE => 'TINYTEXT'}, newvalue => {TYPE => 'TINYTEXT'}, ], @@ -1281,23 +1345,34 @@ sub get_type_ddl { =item C - Description: Public method to convert abstract (database-generic) field - specifiers to database-specific data types suitable for use - in a C or C SQL statment. If no - database-specific field type has been defined for the given - field type, then it will just return the same field type. - Parameters: a hash or a reference to a hash of a field containing the - following keys: C (required), C (optional), - C (optional), C (optional), C - (optional) - Returns: a DDL string suitable for describing a field in a - C or C SQL statement +=over + +=item B + +Public method to convert abstract (database-generic) field specifiers to +database-specific data types suitable for use in a C or +C SQL statment. If no database-specific field type has been +defined for the given field type, then it will just return the same field type. + +=item B + +=over + +=item C<$def> - A reference to a hash of a field containing the following keys: +C (required), C (optional), C (optional), +C (optional), C (optional) + +=back + +-item B + +A DDL string suitable for describing a field in a C or +C SQL statement =cut my $self = shift; my $finfo = (@_ == 1 && ref($_[0]) eq 'HASH') ? $_[0] : { @_ }; - my $type = $finfo->{TYPE}; die "A valid TYPE was not specified for this column." unless ($type); @@ -1308,19 +1383,91 @@ sub get_type_ddl { $default = $self->{db_specific}->{$default}; } - my $fkref = $self->{enable_references} ? $finfo->{REFERENCES} : undef; my $type_ddl = $self->convert_type($type); # DEFAULT attribute must appear before any column constraints # (e.g., NOT NULL), for Oracle $type_ddl .= " DEFAULT $default" if (defined($default)); $type_ddl .= " NOT NULL" if ($finfo->{NOTNULL}); $type_ddl .= " PRIMARY KEY" if ($finfo->{PRIMARYKEY}); - $type_ddl .= "\n\t\t\t\tREFERENCES $fkref" if $fkref; return($type_ddl); } #eosub--get_type_ddl + +# Used if you want to display the DDL to the user, as opposed to actually +# use it in the database. +sub get_display_ddl { + my ($self, $table, $column, $def) = @_; + my $ddl = $self->get_type_ddl($def); + if ($def->{REFERENCES}) { + $ddl .= $self->get_fk_ddl($table, $column, $def->{REFERENCES}); + } + return $ddl; +} + +sub get_fk_ddl { +=item C<_get_fk_ddl> + +=over + +=item B + +Protected method. Translates the C item of a column into SQL. + +=item B + +=over + +=item C<$table> - The name of the table the reference is from. +=item C<$column> - The name of the column the reference is from +=item C<$references> - The C hashref from a column. + +=back + +Returns: SQL for to define the foreign key, or an empty string + if C<$references> is undefined. + +=cut + + my ($self, $table, $column, $references) = @_; + return "" if !$references; + + my $update = $references->{UPDATE} || 'CASCADE'; + my $delete = $references->{DELETE} || 'RESTRICT'; + my $to_table = $references->{TABLE} || die "No table in reference"; + my $to_column = $references->{COLUMN} || die "No column in reference"; + my $fk_name = $self->_get_fk_name($table, $column, $references); + + return "\n CONSTRAINT $fk_name FOREIGN KEY ($column)\n" + . " REFERENCES $to_table($to_column)\n" + . " ON UPDATE $update ON DELETE $delete"; +} + +# Generates a name for a Foreign Key. It's separate from get_fk_ddl +# so that certain databases can override it (for shorter identifiers or +# other reasons). +sub _get_fk_name { + my ($self, $table, $column, $references) = @_; + my $to_table = $references->{TABLE}; + my $to_column = $references->{COLUMN}; + return "fk_${table}_${column}_${to_table}_${to_column}"; +} + +sub _get_add_fk_sql { + my ($self, $table, $column, $new_def) = @_; + + my $fk_string = $self->get_fk_ddl($table, $column, $new_def->{REFERENCES}); + return ("ALTER TABLE $table ADD $fk_string"); +} + +sub _get_drop_fk_sql { + my ($self, $table, $column, $old_def) = @_; + my $fk_name = $self->_get_fk_name($table, $column, $old_def->{REFERENCES}); + + return ("ALTER TABLE $table DROP CONSTRAINT $fk_name"); +} + sub convert_type { =item C @@ -1363,17 +1510,27 @@ sub get_table_list { Description: Public method for discovering what tables should exist in the Bugzilla database. + Parameters: none - Returns: an array of table names + + Returns: An array of table names. The tables specified + in L will come first, in order. The + rest of the tables will be in random order. =cut my $self = shift; - return(sort(keys %{ $self->{schema} })); + my %schema = %{$self->{schema}}; + my @tables; + foreach my $table (TABLES_FIRST) { + push(@tables, $table); + delete $schema{$table}; + } + push(@tables, keys %schema); + return @tables; +} -} #eosub--get_table_list -#-------------------------------------------------------------------------- sub get_table_columns { =item C @@ -1440,6 +1597,14 @@ sub get_table_ddl { push(@ddl, $index_sql) if $index_sql; } + my %fields = @{$self->{schema}{$table}{FIELDS}}; + foreach my $col (keys %fields) { + my $def = $fields{$col}; + if ($def->{REFERENCES}) { + push(@ddl, $self->_get_add_fk_sql($table, $col, $def)); + } + } + push(@ddl, @{ $self->{schema}{$table}{DB_EXTRAS} }) if (ref($self->{schema}{$table}{DB_EXTRAS})); @@ -1653,6 +1818,15 @@ sub get_alter_column_ddl { push(@statements, "ALTER TABLE $table DROP PRIMARY KEY"); } + # If we went from not having an FK to having an FK + # XXX For right now, you can't change an FK's actual definition. + if (!$old_def->{REFERENCES} && $new_def->{REFERENCES}) { + push(@statements, $self->_get_add_fk_sql($table, $column, $new_def)); + } + elsif ($old_def->{REFERENCES} && !$new_def->{REFERENCES}) { + push(@statements, $self->_get_drop_fk_sql($table, $column, $old_def)); + } + return @statements; } @@ -2040,14 +2214,31 @@ sub columns_equal { $col_one->{TYPE} = uc($col_one->{TYPE}); $col_two->{TYPE} = uc($col_two->{TYPE}); - my @col_one_array = %$col_one; - my @col_two_array = %$col_two; + # It doesn't work to compare the two REFERENCES items, because + # they look like 'HASH(0xaf3c434)' to diff_arrays--they'll never + # be equal. + my %col_one_def = %$col_one; + delete $col_one_def{REFERENCES}; + my %col_two_def = %$col_two; + delete $col_two_def{REFERENCES}; + + my @col_one_array = %col_one_def; + my @col_two_array = %col_two_def; my ($removed, $added) = diff_arrays(\@col_one_array, \@col_two_array); - # If there are no differences between the arrays, - # then they are equal. - return !scalar(@$removed) && !scalar(@$added) ? 1 : 0; + # If there are no differences between the arrays, then they are equal. + my $defs_identical = !scalar(@$removed) && !scalar(@$added); + + # If the basic definitions are identical, we still want to check + # if the two foreign key definitions are different. + my @fk_array_one = %{$col_one->{REFERENCES} || {}}; + my @fk_array_two = %{$col_two->{REFERENCES} || {}}; + my ($fk_removed, $fk_added) = + diff_arrays(\@fk_array_one, \@fk_array_two); + my $fk_identical = !scalar(@$fk_removed) && !scalar(@$fk_added); + + return $defs_identical && $fk_identical ? 1 : 0; } diff --git a/Bugzilla/DB/Schema/Mysql.pm b/Bugzilla/DB/Schema/Mysql.pm index 358137ea5..eb7cd3c87 100644 --- a/Bugzilla/DB/Schema/Mysql.pm +++ b/Bugzilla/DB/Schema/Mysql.pm @@ -176,9 +176,17 @@ sub get_alter_column_ddl { # keys are not allowed. delete $new_def_copy{PRIMARYKEY}; } + # CHANGE COLUMN doesn't support REFERENCES + delete $new_def_copy{REFERENCES}; my $new_ddl = $self->get_type_ddl(\%new_def_copy); my @statements; + + # Drop the FK if the new definition doesn't have one. + if ($old_def->{REFERENCES} && !$new_def->{REFERENCES}) { + push(@statements, $self->_get_drop_fk_sql($table, $column, $old_def)); + } + push(@statements, "UPDATE $table SET $column = $set_nulls_to WHERE $column IS NULL") if defined $set_nulls_to; push(@statements, "ALTER TABLE $table CHANGE COLUMN @@ -187,9 +195,30 @@ sub get_alter_column_ddl { # Dropping a PRIMARY KEY needs an explicit DROP PRIMARY KEY push(@statements, "ALTER TABLE $table DROP PRIMARY KEY"); } + + # Add the FK if the new definition has one and the old definition doesn't. + if ($new_def->{REFERENCES} && !$old_def->{REFERENCES}) { + push(@statements, $self->_get_add_fk_sql($table, $column, $new_def)); + } return @statements; } +sub _get_drop_fk_sql { + my ($self, $table, $column, $old_def) = @_; + my $fk_name = $self->_get_fk_name($table, $column, $old_def->{REFERENCES}); + my @sql = ("ALTER TABLE $table DROP FOREIGN KEY $fk_name"); + my $dbh = Bugzilla->dbh; + + # MySQL requires, and will create, an index on any column with + # an FK. It will name it after the fk, which we never do. + # So if there's an index named after the fk, we also have to delete it. + if ($dbh->bz_index_info_real($table, $fk_name)) { + push(@sql, $self->get_drop_index_ddl($table, $fk_name)); + } + + return @sql; +} + sub get_drop_index_ddl { my ($self, $table, $name) = @_; return ("DROP INDEX \`$name\` ON $table"); diff --git a/Bugzilla/Install/DB.pm b/Bugzilla/Install/DB.pm index 00032d15b..5e6401828 100644 --- a/Bugzilla/Install/DB.pm +++ b/Bugzilla/Install/DB.pm @@ -49,6 +49,39 @@ sub indicate_progress { } } +# This is used before adding a foreign key to a column, to make sure +# that the database won't fail adding the key. +sub check_references { + my ($table, $column, $foreign_table, $foreign_column) = @_; + my $dbh = Bugzilla->dbh; + + my $bad_values = $dbh->selectcol_arrayref( + "SELECT DISTINCT $table.$column + FROM $table LEFT JOIN $foreign_table + ON $table.$column = $foreign_table.$foreign_column + WHERE $foreign_table.$foreign_column IS NULL"); + + if (@$bad_values) { + my $values = join(', ', @$bad_values); + print <bz_add_column('milestones', 'id', {TYPE => 'MEDIUMSERIAL', NOTNULL => 1, PRIMARYKEY => 1}); + # Referential Integrity begins here + check_references('profiles_activity', 'userid', 'profiles', 'userid'); + $dbh->bz_alter_column('profiles_activity', 'userid', + {TYPE => 'INT3', NOTNULL => 1, REFERENCES => + {TABLE => 'profiles', COLUMN => 'userid', DELETE => 'CASCADE'}}); + check_references('profiles_activity', 'who', 'profiles', 'userid'); + $dbh->bz_alter_column('profiles_activity', 'who', + {TYPE => 'INT3', NOTNULL => 1, REFERENCES => + {TABLE => 'profiles', COLUMN => 'userid'}}); + check_references('profiles_activity', 'fieldid', 'fielddefs', 'id'); + $dbh->bz_alter_column('profiles_activity', 'fieldid', + {TYPE => 'INT3', NOTNULL => 1, REFERENCES => + {TABLE => 'fielddefs', COLUMN => 'id'}}); + ################################################################ # New --TABLE-- changes should go *** A B O V E *** this point # ################################################################ -- cgit v1.2.3-24-g4f1b