How to Search for a Null Value: Difference between revisions
Jump to navigation
Jump to search
m (Mtulig moved page How to search for a null value to How to Search for a Null Value without leaving a redirect) |
No edit summary |
||
Line 10: | Line 10: | ||
Find all ''Lecythis ''specimens without images: | Find all ''Lecythis ''specimens without images: | ||
:[[File:ClipCapIt-151123-162641.PNG]] | |||
:[[File:ClipCapIt-151123-162658.PNG]] |
Revision as of 21:24, 23 November 2015
It is not uncommon to want to search for records with nothing in a particular field. Which search string you use will depend on what it is that you don’t want to find. In EMu, the exclamation mark specifies NOT. Thus:
!+ in an attachment field will return all records where there is no attachment in that field.
!* in any field will return records where there is no value in a field.
Keep in mind that these searches take longer than searches using complete words.
Example
Find all Lecythis specimens without images: