If I'm reading a MySql binlog, can I get an indication of which statements occur in the same transaction?
There's nothing built-in yet, but perhaps this page will provide some help. They provide an awk script that will parse the binary log and provide transaction details, for row-based replication at least. We don't like link-only answers, so I'll post the script itself here:
startdate="2015-01-12 21:40:00"
stopdate="2015-01-12 21:45:00"
logfile="mysqld-bin.000023"
mysqlbinlog --base64-output=decode-rows -vv --start-datetime="$startdate" --stop-datetime="$stopdate" $logfile | awk \
'BEGIN {s_type=""; s_count=0;count=0;insert_count=0;update_count=0;delete_count=0;flag=0;} \
{if(match($0, /#15.*Table_map:.*mapped to number/)) {printf "Timestamp : " $1 " " $2 " Table : " $(NF-4); flag=1} \
else if (match($0, /(### INSERT INTO .*..*)/)) {count=count+1;insert_count=insert_count+1;s_type="INSERT"; s_count=s_count+1;} \
else if (match($0, /(### UPDATE .*..*)/)) {count=count+1;update_count=update_count+1;s_type="UPDATE"; s_count=s_count+1;} \
else if (match($0, /(### DELETE FROM .*..*)/)) {count=count+1;delete_count=delete_count+1;s_type="DELETE"; s_count=s_count+1;} \
else if (match($0, /^(# at) /) && flag==1 && s_count>0) {print " Query Type : "s_type " " s_count " row(s) affected" ;s_type=""; s_count=0; } \
else if (match($0, /^(COMMIT)/)) {print "[Transaction total : " count " Insert(s) : " insert_count " Update(s) : " update_count " Delete(s) : " \
delete_count "] \n+----------------------+----------------------+----------------------+----------------------+"; \
count=0;insert_count=0;update_count=0; delete_count=0;s_type=""; s_count=0; flag=0} } '