Raise error if dbsqlsend fails

Author: andyundso

CHANGELOG.md

@@ -3,6 +3,7 @@
 * Drop support for Ruby < 2.7
 * Drop support for SQL Server < 2017
 * Drop support for FreeTDS < 1.0
+* Raise error if FreeTDS is unable to sent command buffer to the server
 
 ## 2.1.7
 * Add Ruby 3.3 to the cross compile list

ext/tiny_tds/client.c

@@ -299,8 +299,7 @@ static VALUE rb_tinytds_execute(VALUE self, VALUE sql) {
   REQUIRE_OPEN_CLIENT(cwrap);
   dbcmd(cwrap->client, StringValueCStr(sql));
   if (dbsqlsend(cwrap->client) == FAIL) {
-    rb_warn("TinyTds: dbsqlsend() returned FAIL.\n");
-    return Qfalse;
+    rb_raise(cTinyTdsError, "failed dbsqlsend() function");
   }
   cwrap->userdata->dbsql_sent = 1;
   result = rb_tinytds_new_result_obj(cwrap);