# HG changeset patch
# User Adam Chlipala <adamc@hcoop.net>
# Date 1228663555 18000
# Node ID 7417c4b57aebcc2d690630442e555919e674196e
# Parent  f31aa2a3a72d8f243227839cb1dc8182f4bad70a
Sequences

diff -r f31aa2a3a72d -r 7417c4b57aeb doc/manual.tex
--- a/doc/manual.tex	Sun Dec 07 10:24:23 2008 -0500
+++ b/doc/manual.tex	Sun Dec 07 10:25:55 2008 -0500
@@ -1187,4 +1187,14 @@
   \mt{val} \; \mt{delete} : \mt{fields} ::: \{\mt{Type}\} \to \mt{sql\_table} \; \mt{fields} \to \mt{sql\_exp} \; [\mt{T} = \mt{fields}] \; [] \; [] \; \mt{bool} \to \mt{dml}
 \end{array}$$
 
+\subsubsection{Sequences}
+
+SQL sequences are counters with concurrency control, often used to assign unique IDs.  Ur/Web supports them via a simple interface.  The only way to create a sequence is with the $\mt{sequence}$ declaration form.
+
+$$\begin{array}{l}
+  \mt{type} \; \mt{sql\_sequence} \\
+  \mt{val} \; \mt{nextval} : \mt{sql\_sequence} \to \mt{transaction} \; \mt{int}
+\end{array}$$
+
+
 \end{document}
\ No newline at end of file