Hi,

On 2018-03-28 20:26:48 +0900, Yugo Nagata wrote:
> diff --git a/doc/src/sgml/ref/lock.sgml b/doc/src/sgml/ref/lock.sgml
> index b2c7203..96d477c 100644
> --- a/doc/src/sgml/ref/lock.sgml
> +++ b/doc/src/sgml/ref/lock.sgml
> @@ -46,6 +46,11 @@ LOCK [ TABLE ] [ ONLY ] <replaceable 
> class="parameter">name</replaceable> [ * ]
>    </para>
>  
>    <para>
> +   When a view is specified to be locked, all relations appearing in the view
> +   definition query are also locked recursively with the same lock mode. 
> +  </para>

Trailing space added. I'd remove "specified to be" from the sentence.

I think mentioning how this interacts with permissions would be a good
idea too. Given how operations use the view's owner to recurse, that's
not obvious. Should also explain what permissions are required to do the
operation on the view.


> @@ -86,15 +92,17 @@ RangeVarCallbackForLockTable(const RangeVar *rv, Oid 
> relid, Oid oldrelid,
>               return;                                 /* woops, concurrently 
> dropped; no permissions
>                                                                * check */
>  
> -     /* Currently, we only allow plain tables to be locked */
> -     if (relkind != RELKIND_RELATION && relkind != RELKIND_PARTITIONED_TABLE)
> +

This newline looks spurious to me.


>  /*
> + * Apply LOCK TABLE recursively over a view
> + *
> + * All tables and views appearing in the view definition query are locked
> + * recursively with the same lock mode.
> + */
> +
> +typedef struct
> +{
> +     Oid root_reloid;
> +     LOCKMODE lockmode;
> +     bool nowait;
> +     Oid viewowner;
> +     Oid viewoid;
> +} LockViewRecurse_context;

Probably wouldn't hurt to pgindent the larger changes in the patch.


> +static bool
> +LockViewRecurse_walker(Node *node, LockViewRecurse_context *context)
> +{
> +     if (node == NULL)
> +             return false;
> +
> +     if (IsA(node, Query))
> +     {
> +             Query           *query = (Query *) node;
> +             ListCell        *rtable;
> +
> +             foreach(rtable, query->rtable)
> +             {
> +                     RangeTblEntry   *rte = lfirst(rtable);
> +                     AclResult                aclresult;
> +
> +                     Oid relid = rte->relid;
> +                     char relkind = rte->relkind;
> +                     char *relname = get_rel_name(relid);
> +
> +                     /* The OLD and NEW placeholder entries in the view's 
> rtable are skipped. */
> +                     if (relid == context->viewoid &&
> +                             (!strcmp(rte->eref->aliasname, "old") || 
> !strcmp(rte->eref->aliasname, "new")))
> +                             continue;
> +
> +                     /* Currently, we only allow plain tables or views to be 
> locked. */
> +                     if (relkind != RELKIND_RELATION && relkind != 
> RELKIND_PARTITIONED_TABLE &&
> +                             relkind != RELKIND_VIEW)
> +                             continue;
> +
> +                     /* Check infinite recursion in the view definition. */
> +                     if (relid == context->root_reloid)
> +                             ereport(ERROR,
> +                                             
> (errcode(ERRCODE_INVALID_OBJECT_DEFINITION),
> +                                             errmsg("infinite recursion 
> detected in rules for relation \"%s\"",
> +                                                             
> get_rel_name(context->root_reloid))));

Hm, how can that happen? And if it can happen, why can it only happen
with the root relation?

Greetings,

Andres Freund

Reply via email to