[Dept of swatting flies with sledgehammers]
Peter Eisentraut <peter_e@gmx.net> writes:
> One of these days we should decide on a spelling of "indexes" vs
> "indices".
I'd vote for "indexes", first on the practical grounds that it's a more
sensible spelling, and secondly on the grounds that the Oxford English
Dictionary agrees. Its entry for the noun index has:
Index: PL indexes and indices. In current use the plural is indices in
senses 8, 9, and usually in other senses except 5, in which indexes is
usual.
1. The fore-finger. (Now chiefly Anat.)
2. A piece of wood, metal, or the like which serves as a pointer.
3. The hand of a clock, watch, or sundial. (Now rare)
4. That which serves to direct ... a guiding principle.
5. (a) A table of contents, preface, or prologue (Obs). (b) An
alphabetical list, placed (usually) at the end of a book, of the names,
subjects, etc. occurring in it, with indication of the places in which
they occur.
6. Spec. (short for Index librorum prohibitorum) The list of books which
Roman Catholics are forbidden to read.
7. A "hand" marker in printing. (Obs)
8. Math. (a) a number placed above and to the right of another quantity
to denote a power or root. (b) the integral part of a logarithm. (Obs)
9. In various sciences, a number or formula expressing some property of
the thing in question. (ex. Index of refraction)
(I've abbreviated the definitions other than sense 5b.)
I'd say that the use of "index" in database work clearly falls under
sense 5b, and so "indexes" is the usual plural according to the OED.
The habit of using "indices" in the Postgres documentation seems to go
back to the Berkeley days. Possibly the Berkeley boys were familiar
with sense 8 and/or 9 and so tended to use that plural.
regards, tom lane