Mercurial > urweb
changeset 1683:be1ed46d73e2
Mention convention for parens in selected expressions
author | Adam Chlipala <adam@chlipala.net> |
---|---|
date | Fri, 03 Feb 2012 08:30:56 -0500 (2012-02-03) |
parents | ac141fbb313a |
children | 9dd8d47c3e58 |
files | doc/manual.tex |
diffstat | 1 files changed, 1 insertions(+), 1 deletions(-) [+] |
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--- a/doc/manual.tex Thu Feb 02 11:40:10 2012 -0500 +++ b/doc/manual.tex Fri Feb 03 08:30:56 2012 -0500 @@ -2178,7 +2178,7 @@ Additionally, an SQL expression may be inserted into normal Ur code with the syntax $(\mt{SQL} \; E)$ or $(\mt{WHERE} \; E)$. Similar shorthands exist for other nonterminals, with the prefix $\mt{FROM}$ for $\mt{FROM}$ items and $\mt{SELECT1}$ for pre-queries. -Unnamed expression columns in $\mt{SELECT}$ clauses are assigned consecutive natural numbers, starting with 1. +Unnamed expression columns in $\mt{SELECT}$ clauses are assigned consecutive natural numbers, starting with 1. Any expression in a $p$ position that is enclosed in parentheses is treated as an expression column, rather than a column pulled directly out of a table, even if it is only a field projection. (This distinction affects the record type used to describe query results.) \subsubsection{DML}