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DBIx::DBStag::Constraint(3pm) User Contributed Perl Documentation DBIx::DBStag::Constraint(3pm)


DBIx::DBStag::Constraint - recursive structure for representing query constraints



A constraint is a recursive structure for representing query constraints;

  AND ---  x=1
     \---- OR   ---  y>2
             \-----  boolfunc(z)

A constraint is either a bool (AND, OR, NOT) with >0 children, or it can be a leaf node representing an atomic constraint

the constraint corresponds to a SQLTemplate option block; eg

  [ name LIKE &name& ]
  [ name => &name& ]
  [ start > &min_start& ]
  [ start => &start& ]
  [ somefunc(&x&) ]
  [ somefunc(&x&, &y&) ]
  [ somefunc(t.col, &x&, &y&) => &z& ]

the constraint consists of an operator (represented by => in the option block). If no => is present, then it is a simple variable binding.

A constraint can consist of multiple variable bindings




Chris Mungall <>


Copyright (c) 2003 Chris Mungall

This module is free software. You may distribute this module under the same terms as perl itself

2016-05-29 perl v5.22.2