index de0a98f6d952752031abb20a45cb0cbcce375813..9126c18d0e175b5c6ab032ffea46bd55a452b15b 100644 (file)
* target page:
*
* - That every "real" data item is less than or equal to the high key, which
- * is an upper bound on the items on the pages (where there is a high key at
- * all -- pages that are rightmost lack one).
+ * is an upper bound on the items on the page. Data items should be
+ * strictly less than the high key when the page is an internal page.
*
- * - That within the page, every "real" item is less than or equal to the item
- * immediately to its right, if any (i.e., that the items are in order within
- * the page, so that the binary searches performed by index scans are sane).
+ * - That within the page, every data item is strictly less than the item
+ * immediately to its right, if any (i.e., that the items are in order
+ * within the page, so that the binary searches performed by index scans are
+ * sane).
*
- * - That the last item stored on the page is less than or equal to the first
- * "real" data item on the page to the right (if such a first item is
+ * - That the last data item stored on the page is strictly less than the
+ * first data item on the page to the right (when such a first item is
* available).
*
- * - That tuples report that they have the expected number of attributes.
- * INCLUDE index pivot tuples should not contain non-key attributes.
+ * - Various checks on the structure of tuples themselves. For example, check
+ * that non-pivot tuples have no truncated attributes.
*
* Furthermore, when state passed shows ShareLock held, function also checks:
*
- * - That all child pages respect downlinks lower bound.
+ * - That all child pages respect strict lower bound from parent's pivot
+ * tuple.
*
* - That downlink to block was encountered in parent where that's expected.
* (Limited to heapallindexed readonly callers.)