fix database not exist

helper/bench/prepare.sh

@@ -7,4 +7,4 @@ git clone https://github.com/dtm-labs/dtm.git && cd dtm && git checkout alpha &&
 echo 'all prepared. you shoud run following commands to test in different terminal'
 echo
 echo 'cd dtf && go run helper/bench/main.go redis|boltdb|db'
-echo 'cd dtf/helper && bench/run-redis|boltdb|mysql.sh'
+echo 'cd dtf && ./helper/bench/test-redis|boltdb|mysql.sh'

helper/bench/svr/http.go

@@ -73,7 +73,9 @@ var sqls = 1
 // PrepareBenchDB prepares db data for bench
 func PrepareBenchDB() {
 	db := pdbGet()
-	_, err := dtmimp.DBExec(db, "drop table if exists dtm_busi.user_account_log")
+	_, err := dtmimp.DBExec(db, "CREATE DATABASE if not exists dtm_busi")
+	logger.FatalIfError(err)
+	_, err = dtmimp.DBExec(db, "drop table if exists dtm_busi.user_account_log")
 	logger.FatalIfError(err)
 	_, err = dtmimp.DBExec(db, `create table if not exists dtm_busi.user_account_log (
 	id      INT(11) AUTO_INCREMENT PRIMARY KEY,