diff options
Diffstat (limited to 'src/include/access/rmgrdesc_utils.h')
-rw-r--r-- | src/include/access/rmgrdesc_utils.h | 44 |
1 files changed, 0 insertions, 44 deletions
diff --git a/src/include/access/rmgrdesc_utils.h b/src/include/access/rmgrdesc_utils.h index bd414699f21..c754d55621b 100644 --- a/src/include/access/rmgrdesc_utils.h +++ b/src/include/access/rmgrdesc_utils.h @@ -12,50 +12,6 @@ #ifndef RMGRDESC_UTILS_H_ #define RMGRDESC_UTILS_H_ -/* - * Guidelines for rmgrdesc routine authors: - * - * The goal of these guidelines is to avoid gratuitous inconsistencies across - * each rmgr, and to allow users to parse desc output strings without too much - * difficulty. This is not an API specification or an interchange format. - * (Only heapam and nbtree desc routines follow these guidelines at present, - * in any case.) - * - * Record descriptions are similar to JSON style key/value objects. However, - * there is no explicit "string" type/string escaping. Top-level { } brackets - * should be omitted. For example: - * - * snapshotConflictHorizon: 0, flags: 0x03 - * - * Record descriptions may contain variable-length arrays. For example: - * - * nunused: 5, unused: [1, 2, 3, 4, 5] - * - * Nested objects are supported via { } brackets. They generally appear - * inside variable-length arrays. For example: - * - * ndeleted: 0, nupdated: 1, deleted: [], updated: [{ off: 45, nptids: 1, ptids: [0] }] - * - * Try to output things in an order that faithfully represents the order of - * fields from the underlying physical WAL record struct. Key names should be - * unique (at the same nesting level) to make parsing easy. It's a good idea - * if the number of items in the array appears before the array. - * - * It's okay for individual WAL record types to invent their own conventions. - * For example, Heap2's PRUNE record descriptions use a custom array format - * for the record's "redirected" field: - * - * ... redirected: [1->4, 5->9], dead: [10, 11], unused: [3, 7, 8] - * - * Arguably the desc routine should be using object notation for this instead. - * However, there is value in using a custom format when it conveys useful - * information about the underlying physical data structures. - * - * This ad-hoc format has the advantage of being close to the format used for - * the "dead" and "unused" arrays (which follow the standard desc convention - * for page offset number arrays). It suggests that the "redirected" elements - * shown are just pairs of page offset numbers (which is how it really works). - */ extern void array_desc(StringInfo buf, void *array, size_t elem_size, int count, void (*elem_desc) (StringInfo buf, void *elem, void *data), void *data); |