Merging
Works by: Drag and drop, right-click
Hot keys: M
Source requirements: Exactly one source term required
Target requirement: One target required
It is possible to merge two concepts into one. When term A is merged into
term B, the following things happen:
- A's id is assigned as an alternate id of B
- All of A's synonyms are copied to B
- All of A's dbxrefs are copied to B
- A & B's comments are merged (see Merging Comments & Definitions )
- A & B's definitions are merged (see Merging Comments & Definitions )
- A's name is assigned as an exact synonym of B.
- All of A's parents become parents of B (see Caveats )
- All of A's children become parents of B (see Caveats )
- All of A's parent relationships are deleted
- All of A's child relationships are deleted
- A is destroyed (see caveats)
It is impossible to create a cycle by merging, because any potentially cyclic
links are not copied to the target term. See caveats for
potential pitfalls of this behavior.
To merge two terms, select the source term you would
like to merge (if a term appears in the ontology editor panel multiple times because
of multiple parentage, it does not matter which one you choose). Indicate the
target term by right-clicking or drag and drop.
Choose "Merge" from the right-click menu or drag and drop popup menu. The
terms will be merged.
Merging Comments & Definitions
When two terms are merged, the source term's comments are
merged with the target term's comments, and the source term's definition is
merged with the target term's definition. When merging comments and definitions,
the following rules are used:
- If both the source term & target term have a blank comment or
definition, the merged term's comment or definition is left blank.
- If the source term's comment or definition is blank, the target term's
comment or definition is used
- If the target term's comment or definition is blank, the source term's
comment or definition is used
- If both the source and target term have a comment or definition defined,
the comment or definition of both the source and target term are concatenated
together. This concatenated comment or definition becomes the comment or
definition for the merged term.
Caveats
- When two terms are merged, only one "survives". The
other term's id only lives on as a secondary id. Therefore, it's
very important to consider which term should be the source term (the one that
is destroyed) and which is the target term (the one that lives on).
- Any term can be merged with any other term. However,
some merges could result in a horrible mess of cycles, because the merged term
gets all the parents and children of the source term (for example, if a
term was merged with a grandchild, a cycle is certain). Therefore, OBO-Edit will simply remove any cyclic links when
a merge occurs. Since potential cycles can be very hard for humans to detect, you may
be surprised that certain relationships from the source term have not
carried over to the merged term. Always check to make sure no critical links
have disappeared after a merge! (The good news: OBO-Edit will never delete
a link from the target term; it will only choose to not copy some
links from the source term).
Hotkeys
Hold down the "M" key while dragging to specify the
"Merge" operation. The title above the dragged terms will change from
"Dragging..." to "Merge...":

When the term is dropped, the source and target term
will be merged automatically.