message: Returning a ConstantExpressin with BLOB just for strings (T_PGString).
diff: @@ -17,8 +17,10 @@ unique_ptr<ParsedExpression> Transformer::TransformTypeCast(PGTypeCast *root) {
  //check for a constant BLOB value, then return ConstantExpression with BLOB
  if(target_type == SQLType::BLOB && root->arg->type == T_PGAConst) {
  PGAConst *c = reinterpret_cast<PGAConst *>(root->arg);
  + if(c->val.type == T_PGString) {
  return make_unique<ConstantExpression>(SQLType::BLOB, Value::BLOB(string(c->val.val.str)));
  }
  + }
  // transform the expression node
  auto expression = TransformExpression(root->arg);
  