RE: Logical Replication of sequences

Dear Vignesh,

Thanks for updating the patch. Here are comments for 0002.

```
+       if (pubrelkind == '\0')
+               return;
```

Instead of adding this part, can we provide another function which only checks
the type mismatch? New one can be called from CreateSubscription() and
AlterSubscription_refresh().

```
+#include "nodes/primnodes.h"
...
+typedef struct SubscriptionRelKind
+{
+       RangeVar   *rv;
+       char            relkind;
+}
```

The data structure is used in subscriptioncmds.c. Can we move the definition to
the file?
Also, `relkind` indicates the type of relation on publisher. Can you clarify
the point like `relkind_on_pub`?

Best regards,
Hayato Kuroda
FUJITSU LIMITED