.\" Automatically generated by Pod::Man 2.28 (Pod::Simple 3.28) .\" .\" Standard preamble: .\" ======================================================================== .de Sp \" Vertical space (when we can't use .PP) .if t .sp .5v .if n .sp .. .de Vb \" Begin verbatim text .ft CW .nf .ne \\$1 .. .de Ve \" End verbatim text .ft R .fi .. .\" Set up some character translations and predefined strings. \*(-- will .\" give an unbreakable dash, \*(PI will give pi, \*(L" will give a left .\" double quote, and \*(R" will give a right double quote. \*(C+ will .\" give a nicer C++. Capital omega is used to do unbreakable dashes and .\" therefore won't be available. \*(C` and \*(C' expand to `' in nroff, .\" nothing in troff, for use with C<>. .tr \(*W- .ds C+ C\v'-.1v'\h'-1p'\s-2+\h'-1p'+\s0\v'.1v'\h'-1p' .ie n \{\ . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} .el\{\ . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\} .\" .\" Escape single quotes in literal strings from groff's Unicode transform. .ie \n(.g .ds Aq \(aq .el .ds Aq ' .\" .\" If the F register is turned on, we'll generate index entries on stderr for .\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index .\" entries marked with X<> in POD. Of course, you'll have to process the .\" output yourself in some meaningful fashion. .\" .\" Avoid warning from groff about undefined register 'F'. .de IX .. .nr rF 0 .if \n(.g .if rF .nr rF 1 .if (\n(rF:(\n(.g==0)) \{ . if \nF \{ . de IX . tm Index:\\$1\t\\n%\t"\\$2" .. . if !\nF==2 \{ . nr % 0 . nr F 2 . \} . \} .\} .rr rF .\" .\" Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2). .\" Fear. Run. Save yourself. No user-serviceable parts. . \" fudge factors for nroff and troff .if n \{\ . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] \fP .\} .if t \{\ . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff .if n \{\ . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} .if t \{\ . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents .ds : \\k:\h'-(\\n(.wu*8/10-\*(#H+.1m+\*(#F)'\v'-\*(#V'\z.\h'.2m+\*(#F'.\h'|\\n:u'\v'\*(#V' .ds 8 \h'\*(#H'\(*b\h'-\*(#H' .ds o \\k:\h'-(\\n(.wu+\w'\(de'u-\*(#H)/2u'\v'-.3n'\*(#[\z\(de\v'.3n'\h'|\\n:u'\*(#] .ds d- \h'\*(#H'\(pd\h'-\w'~'u'\v'-.25m'\f2\(hy\fP\v'.25m'\h'-\*(#H' .ds D- D\\k:\h'-\w'D'u'\v'-.11m'\z\(hy\v'.11m'\h'|\\n:u' .ds th \*(#[\v'.3m'\s+1I\s-1\v'-.3m'\h'-(\w'I'u*2/3)'\s-1o\s+1\*(#] .ds Th \*(#[\s+2I\s-2\h'-\w'I'u*3/5'\v'-.3m'o\v'.3m'\*(#] .ds ae a\h'-(\w'a'u*4/10)'e .ds Ae A\h'-(\w'A'u*4/10)'E . \" corrections for vroff .if v .ds ~ \\k:\h'-(\\n(.wu*9/10-\*(#H)'\s-2\u~\d\s+2\h'|\\n:u' .if v .ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'\v'-.4m'^\v'.4m'\h'|\\n:u' . \" for low resolution devices (crt and lpr) .if \n(.H>23 .if \n(.V>19 \ \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} .rm #[ #] #H #V #F C .\" ======================================================================== .\" .IX Title "Alzabo::ForeignKey 3pm" .TH Alzabo::ForeignKey 3pm "2015-05-24" "perl v5.20.2" "User Contributed Perl Documentation" .\" For nroff, turn off justification. Always turn off hyphenation; it makes .\" way too many mistakes in technical documents. .if n .ad l .nh .SH "NAME" Alzabo::ForeignKey \- Foreign key (relation) objects .SH "SYNOPSIS" .IX Header "SYNOPSIS" .Vb 1 \& use Alzabo::ForeignKey; \& \& foreach my $fk ($table\->foreign_keys) \& { \& print $fk\->cardinality; \& } .Ve .SH "DESCRIPTION" .IX Header "DESCRIPTION" A foreign key is an object defined by several properties. It represents a relationship from a column or columns in one table to a column or columns in another table. .PP This relationship is defined by its cardinality (one to one, one to many, or many to one) and its dependencies (whether or not table X is dependent on table Y, and vice versa). .PP Many to many relationships are not allowed. However, you may indicate such a relationship when using the Alzabo::Create::Schema\->add_relation method method, and it will create the necessary intermediate linking table for you. .SH "METHODS" .IX Header "METHODS" .SS "table_from" .IX Subsection "table_from" .SS "table_to" .IX Subsection "table_to" Returns the relevant \f(CW\*(C`Alzabo::Table\*(C'\fR object. .SS "columns_from" .IX Subsection "columns_from" .SS "columns_to" .IX Subsection "columns_to" Returns the relevant \f(CW\*(C`Alzabo::Column\*(C'\fR object(s) for the property as an array. .SS "column_pairs" .IX Subsection "column_pairs" Returns an array of array references. The references are to two column array of \f(CW\*(C`Alzabo::Column\*(C'\fR objects. These two columns correspond in the tables being linked together. .SS "cardinality" .IX Subsection "cardinality" Returns a two element array containing the two portions of the cardinality of the relationship. Each portion will be either '1' or \&'n'. .SS "from_is_dependent" .IX Subsection "from_is_dependent" .SS "to_is_dependent" .IX Subsection "to_is_dependent" Returns a boolean value indicating whether there is a dependency from one table to the other. .SS "is_one_to_one" .IX Subsection "is_one_to_one" .SS "is_one_to_many" .IX Subsection "is_one_to_many" .SS "is_many_to_one" .IX Subsection "is_many_to_one" Returns a boolean value indicating what kind of relationship the object represents. .SS "is_same_relationship_as ($fk)" .IX Subsection "is_same_relationship_as ($fk)" Given a foreign key object, this returns true if the two objects represent the same relationship. However, the two objects may represent the same relationship from different table's points of view. .SS "id" .IX Subsection "id" Returns a string uniquely identifying the foreign key. .SS "comment" .IX Subsection "comment" Returns the comment associated with the foreign key object, if any. .SH "AUTHOR" .IX Header "AUTHOR" Dave Rolsky,