Cast till decimal bör hjälpa :-
mysql> select cast( "5.89872212195226e-05" as decimal(65,30)); +--------------------------------------------------+ | cast( "5.89872212195226e-05" as decimal(65,30)) | +--------------------------------------------------+ | 0.000058987221219522600000000000 | +--------------------------------------------------+
Exempel på jämförelse :-
mysql> select least( 4, cast("5.89872212195226e-05" as decimal(65,30)) ); +------------------------------------------------------------+ | least( 4, cast("5.89872212195226e-05" as decimal(65,30)) ) | +------------------------------------------------------------+ | 0.000058987221219522600000000000 | +------------------------------------------------------------+
Exempel på användning :-
MIN(cast( ... as decimal(65,30)))