The following bug has been logged on the website:
Bug reference:      14478
Logged by:          Nathanael TERRIEN
Email address:      nte(at)mustinformatique(dot)fr
PostgreSQL version: 9.6.1
Operating system:   Windows
Description:        
Not sure if a bug or if I'm missing something but this query produces weird
results with TRIM and TRIM:
SELECT DISTINCT TRIM(TRAILING FROM 'cnam_lpp_histo_io','_io') AS "A"
	,RTRIM('cnam_lpp_histo_io','_io') AS "B"
	,REPLACE('cnam_lpp_histo_io','_io','') AS "C"
	,REGEXP_REPLACE('cnam_lpp_histo_io','_io$','') AS "D";
Results A and B seems wrong to me (C and D are OK):
A=cnam_lpp_hist
B=cnam_lpp_hist
C=cnam_lpp_histo
D=cnam_lpp_histo