SELECT 

rc1.rc_user_text,

rc1.rc_title,

min(rc1.rc_timestamp) as 91_197_23_timestamp,

min(r1.rev_timestamp) as abc10_timestamp

FROM 

recentchanges_compat as rc1,

revision_compat as r1

WHERE 

rc1.rc_user_text LIKE "Jmk"

AND rc1.rc_namespace=0

AND rc1.rc_source NOT IN ("mw.categorize") 

AND rc1.rc_cur_id=r1.rev_page

AND r1.rev_user_text="Abc10"

AND r1.rev_timestamp<rc1.rc_timestamp

GROUP BY rc_title