mysql - Select all unique emails inside a column filled with data -

i have column's field filled kinds of data user request (one request per row).

i need email addresses these users' requests, , placed in column according following format:

[...data...] email: mysql@se.com phone: [...remaining data...] 

i have found question:

select part of table column data in mysql

which provides solution part of problem:

select substr(message,instr(message,'email: ')+7) user_req_log 

however, return unwanted remaining data.

what's efficient way confine results strings need (email addresses) and, @ same time, ignore duplicates?

based on question's solution, may do:

select distinct substr(message,                        @ini_pos:=instr(message,'email: ')+7,                        instr(message,' phone:')-@ini_pos) `user_req_log` 

it may not efficient way, it's similar:

• use 3 parameters of substring(str,pos,len);
• get positions before , after email address through instr(str,substr) or locate(substr,str)/position(substr in str).
• assign variable email's initial position (@ini_pos) , reuse subtract position know ends;
• use distinct return each email once.