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authorPeter Geoghegan2019-05-13 22:53:39 +0000
committerPeter Geoghegan2019-05-13 22:53:39 +0000
commitae7291acbc5ae4c3751615177fc256f9f3399403 (patch)
tree8a67a1936fe81aa9d5e5b1c4b023f7993d6b9437 /src/backend/access/index
parent08ca9d7feca890e97f77ef1fde02d7542a54ac5e (diff)
Standardize ItemIdData terminology.
The term "item pointer" should not be used to refer to ItemIdData variables, since that is needlessly ambiguous. Only ItemPointerData/ItemPointer variables should be called item pointers. To fix, establish the convention that ItemIdData variables should always be referred to either as "item identifiers" or "line pointers". The term "item identifier" already predominates in docs and translatable messages, and so should be the preferred alternative there. Discussion: https://postgr.es/m/CAH2-Wz=c=MZQjUzde3o9+2PLAPuHTpVZPPdYxN=E4ndQ2--8ew@mail.gmail.com
Diffstat (limited to 'src/backend/access/index')
-rw-r--r--src/backend/access/index/indexam.c26
1 files changed, 0 insertions, 26 deletions
diff --git a/src/backend/access/index/indexam.c b/src/backend/access/index/indexam.c
index ae1c87ebadd..0fc9139badb 100644
--- a/src/backend/access/index/indexam.c
+++ b/src/backend/access/index/indexam.c
@@ -38,32 +38,6 @@
* This file contains the index_ routines which used
* to be a scattered collection of stuff in access/genam.
*
- *
- * old comments
- * Scans are implemented as follows:
- *
- * `0' represents an invalid item pointer.
- * `-' represents an unknown item pointer.
- * `X' represents a known item pointers.
- * `+' represents known or invalid item pointers.
- * `*' represents any item pointers.
- *
- * State is represented by a triple of these symbols in the order of
- * previous, current, next. Note that the case of reverse scans works
- * identically.
- *
- * State Result
- * (1) + + - + 0 0 (if the next item pointer is invalid)
- * (2) + X - (otherwise)
- * (3) * 0 0 * 0 0 (no change)
- * (4) + X 0 X 0 0 (shift)
- * (5) * + X + X - (shift, add unknown)
- *
- * All other states cannot occur.
- *
- * Note: It would be possible to cache the status of the previous and
- * next item pointer using the flags.
- *
*-------------------------------------------------------------------------
*/