diff --git a/pkg/api/transaction_categories.go b/pkg/api/transaction_categories.go
index 89b62c73..da25108f 100644
--- a/pkg/api/transaction_categories.go
+++ b/pkg/api/transaction_categories.go
@@ -97,7 +97,7 @@ func (a *TransactionCategoriesApi) CategoryCreateHandler(c *core.Context) (inter
 		}
 	}
 
-	var maxOrderId = 0
+	var maxOrderId int
 
 	if categoryCreateReq.ParentId <= 0 {
 		maxOrderId, err = a.categories.GetMaxDisplayOrder(uid, categoryCreateReq.Type)
diff --git a/pkg/services/accounts.go b/pkg/services/accounts.go
index e3c933fd..ee54f831 100644
--- a/pkg/services/accounts.go
+++ b/pkg/services/accounts.go
@@ -278,13 +278,17 @@ func (s *AccountService) DeleteAccount(uid int64, accountId int64) error {
 
 		exists, err := sess.Cols("uid", "deleted", "source_account_id").Where("uid=? AND deleted=?", uid, false).In("source_account_id", accountAndSubAccountIds).Limit(1).Exist(&models.Transaction{})
 
-		if exists {
+		if err != nil {
+			return err
+		} else if exists {
 			return errs.ErrAccountInUseCannotBeDeleted
 		}
 
 		exists, err = sess.Cols("uid", "deleted", "destination_account_id").Where("uid=? AND deleted=?", uid, false).In("destination_account_id", accountAndSubAccountIds).Limit(1).Exist(&models.Transaction{})
 
-		if exists {
+		if err != nil {
+			return err
+		} else if exists {
 			return errs.ErrAccountInUseCannotBeDeleted
 		}
 
diff --git a/pkg/services/tokens.go b/pkg/services/tokens.go
index e3672c7f..2c914bc8 100644
--- a/pkg/services/tokens.go
+++ b/pkg/services/tokens.go
@@ -248,6 +248,10 @@ func (s *TokenService) createToken(user *models.User, tokenType core.TokenType,
 	jwtToken := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
 	tokenString, err := jwtToken.SignedString([]byte(tokenRecord.Secret))
 
+	if err != nil {
+		return "", nil, err
+	}
+
 	err = s.createTokenRecord(tokenRecord)
 
 	if err != nil {
diff --git a/pkg/services/transaction_categories.go b/pkg/services/transaction_categories.go
index 748c1f2a..9b0f9efa 100644
--- a/pkg/services/transaction_categories.go
+++ b/pkg/services/transaction_categories.go
@@ -286,7 +286,9 @@ func (s *TransactionCategoryService) DeleteCategory(uid int64, categoryId int64)
 
 		exists, err := sess.Cols("uid", "deleted", "category_id").Where("uid=? AND deleted=?", uid, false).In("category_id", categoryAndSubCategoryIds).Limit(1).Exist(&models.Transaction{})
 
-		if exists {
+		if err != nil {
+			return err
+		} else if exists {
 			return errs.ErrTransactionCategoryInUseCannotBeDeleted
 		}
 
diff --git a/pkg/services/transaction_tags.go b/pkg/services/transaction_tags.go
index 0f320dac..c8514256 100644
--- a/pkg/services/transaction_tags.go
+++ b/pkg/services/transaction_tags.go
@@ -214,7 +214,9 @@ func (s *TransactionTagService) DeleteTag(uid int64, tagId int64) error {
 	return s.UserDataDB(uid).DoTransaction(func(sess *xorm.Session) error {
 		exists, err := sess.Cols("uid", "tag_id").Where("uid=? AND tag_id=?", uid, tagId).Limit(1).Exist(&models.TransactionTagIndex{})
 
-		if exists {
+		if err != nil {
+			return err
+		} else if exists {
 			return errs.ErrTransactionTagInUseCannotBeDeleted
 		}
 
diff --git a/pkg/services/transactions.go b/pkg/services/transactions.go
index db36c691..98f6e3ff 100644
--- a/pkg/services/transactions.go
+++ b/pkg/services/transactions.go
@@ -465,6 +465,10 @@ func (s *TransactionService) ModifyTransaction(transaction *models.Transaction,
 
 			has, err = sess.Where("uid=? AND deleted=? AND transaction_time>=? AND transaction_time<=?", transaction.Uid, false, minTransactionTime, maxTransactionTime).OrderBy("transaction_time desc").Limit(1).Get(sameSecondLatestTransaction)
 
+			if err != nil {
+				return err
+			}
+
 			if has && sameSecondLatestTransaction.TransactionTime < maxTransactionTime-1 {
 				transaction.TransactionTime = sameSecondLatestTransaction.TransactionTime + 1
 			} else if has && sameSecondLatestTransaction.TransactionTime == maxTransactionTime-1 {