orm add sqlite3 support, may be support postgres in next commit

orm/db_oracle.go

@@ -4,6 +4,12 @@ type dbBaseOracle struct {
 	dbBase
 }
 
+var _ dbBaser = new(dbBaseOracle)
+
+func (d *dbBase) OperatorSql(operator string) string {
+	return ""
+}
+
 func newdbBaseOracle() dbBaser {
 	b := new(dbBaseOracle)
 	b.ins = b