Re: Values list-of-targetlists patch for comments (was Re:

Joe Conway wrote:

> What if we built an array of A_Const nodes instead of a List? Maybe we
> could use something akin to appendStringInfo()/enlargeStringInfo() to
> build the array of nodes and enlarge it in chunks.

In inval.c you find this:

/*
 * To minimize palloc traffic, we keep pending requests in successively-
 * larger chunks (a slightly more sophisticated version of an expansible
 * array).  All request types can be stored as SharedInvalidationMessage
 * records.  The ordering of requests within a list is never significant.
 */
typedef struct InvalidationChunk
{
    struct InvalidationChunk *next;     /* list link */
    int         nitems;         /* # items currently stored in chunk */
    int         maxitems;       /* size of allocated array in this chunk */
    SharedInvalidationMessage msgs[1];  /* VARIABLE LENGTH ARRAY */
} InvalidationChunk;            /* VARIABLE LENGTH STRUCTURE */

Which might give you an idea ...

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Alvaro Herrera                                http://www.CommandPrompt.com/
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