diff --git a/store/datastore/store.go b/store/datastore/store.go
index bb279ca86..2f4276520 100644
--- a/store/datastore/store.go
+++ b/store/datastore/store.go
@@ -67,6 +67,10 @@ func Open(driver, config string) *sql.DB {
 		log.Errorln(err)
 		log.Fatalln("database connection failed")
 	}
+	if driver == "mysql" {
+		// per issue https://github.com/go-sql-driver/mysql/issues/257
+		db.SetMaxIdleConns(0)
+	}
 
 	setupMeddler(driver)
 
diff --git a/store/migration/mysql/1_init.sql b/store/migration/mysql/1_init.sql
index 0efa421bc..25e5ee2d4 100644
--- a/store/migration/mysql/1_init.sql
+++ b/store/migration/mysql/1_init.sql
@@ -1,6 +1,6 @@
 -- +migrate Up
 
-CREATE TABLE users (
+CREATE TABLE IF NOT EXISTS users (
  user_id     INTEGER PRIMARY KEY AUTO_INCREMENT
 ,user_login  VARCHAR(500)
 ,user_token  VARCHAR(500)
@@ -15,7 +15,7 @@ CREATE TABLE users (
 ,UNIQUE(user_login)
 );
 
-CREATE TABLE repos (
+CREATE TABLE IF NOT EXISTS repos (
  repo_id            INTEGER PRIMARY KEY AUTO_INCREMENT
 ,repo_user_id       INTEGER
 ,repo_owner         VARCHAR(255)
@@ -37,7 +37,7 @@ CREATE TABLE repos (
 ,UNIQUE(repo_full_name)
 );
 
-CREATE TABLE `keys` (
+CREATE TABLE IF NOT EXISTS `keys` (
  key_id      INTEGER PRIMARY KEY AUTO_INCREMENT
 ,key_repo_id INTEGER
 ,key_public  MEDIUMBLOB
@@ -46,7 +46,7 @@ CREATE TABLE `keys` (
 ,UNIQUE(key_repo_id)
 );
 
-CREATE TABLE builds (
+CREATE TABLE IF NOT EXISTS builds (
  build_id        INTEGER PRIMARY KEY AUTO_INCREMENT
 ,build_repo_id   INTEGER
 ,build_number    INTEGER
@@ -72,9 +72,9 @@ CREATE TABLE builds (
 ,UNIQUE(build_number, build_repo_id)
 );
 
-CREATE INDEX ix_build_repo ON builds (build_repo_id);
+CREATE INDEX IF NOT EXISTS ix_build_repo ON builds (build_repo_id);
 
-CREATE TABLE jobs (
+CREATE TABLE IF NOT EXISTS jobs (
  job_id          INTEGER PRIMARY KEY AUTO_INCREMENT
 ,job_node_id     INTEGER
 ,job_build_id    INTEGER
@@ -89,8 +89,8 @@ CREATE TABLE jobs (
 ,UNIQUE(job_build_id, job_number)
 );
 
-CREATE INDEX ix_job_build ON jobs (job_build_id);
-CREATE INDEX ix_job_node  ON jobs (job_node_id);
+CREATE INDEX IF NOT EXISTS ix_job_build ON jobs (job_build_id);
+CREATE INDEX IF NOT EXISTS ix_job_node  ON jobs (job_node_id);
 
 CREATE TABLE IF NOT EXISTS logs (
  log_id     INTEGER PRIMARY KEY AUTO_INCREMENT
diff --git a/store/migration/mysql/2.sql b/store/migration/mysql/2.sql
index 7f3fb8879..4f507f65b 100644
--- a/store/migration/mysql/2.sql
+++ b/store/migration/mysql/2.sql
@@ -3,8 +3,8 @@
 ALTER TABLE repos  ADD COLUMN repo_scm     VARCHAR(25);
 ALTER TABLE builds ADD COLUMN build_deploy VARCHAR(500);
 
-UPDATE repos  SET repo_scm = 'git';
-UPDATE builds SET build_deploy = '';
+UPDATE repos  SET repo_scm = 'git' WHERE repo_scm = null;
+UPDATE builds SET build_deploy = '' WHERE build_deploy = null;
 
 -- +migrate Down