\set ECHO none
remove_provenance

(1 row)
city|why
Berlin|{{Ellen,Susan}}
New York|{{John,Paul}}
Paris|{{Dave,Magdalen},{Dave,Nancy},{Magdalen,Nancy}}
(3 rows)
create_provenance_mapping

(1 row)
remove_provenance

(1 row)
city|why
Berlin|{{Ellen_a,Susan_a},{Ellen_a,Susan_b},{Ellen_b,Susan_a},{Ellen_b,Susan_b}}
New York|{{John_a,Paul_a},{John_a,Paul_b},{John_b,Paul_a},{John_b,Paul_b}}
Paris|{{Dave_a,Magdalen_a},{Dave_a,Magdalen_b},{Dave_a,Nancy_a},{Dave_a,Nancy_b},{Dave_b,Magdalen_a},{Dave_b,Magdalen_b},{Dave_b,Nancy_a},{Dave_b,Nancy_b},{Magdalen_a,Nancy_a},{Magdalen_a,Nancy_b},{Magdalen_b,Nancy_a},{Magdalen_b,Nancy_b}}
(3 rows)