fix unprotected variable in SQL example

diff --git a/doc/doc-docbook/spec.xfpt b/doc/doc-docbook/spec.xfpt
index 530d9e3c493924ca09468cceb8c8814a8b5175af..688f554650534a6b289faa7253fe0862532a025d 100644 (file)
--- a/doc/doc-docbook/spec.xfpt
+++ b/doc/doc-docbook/spec.xfpt
@@ -7779,7 +7779,7 @@ pattern must be an appropriate query for the lookup type, as described in
 chapter &<<CHAPfdlookup>>&. For example:
 .code
 hold_domains = mysql;select domain from holdlist \
-  where domain = '$domain';
+  where domain = '${quote_mysql:$domain}';
 .endd
 In most cases, the data that is looked up is not used (so for an SQL query, for
 example, it doesn't matter what field you select). Exim is interested only in