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diff --git a/doc/src/sgml/rules.sgml b/doc/src/sgml/rules.sgml new file mode 100644 index 00000000000..2dabb3ca35a --- /dev/null +++ b/doc/src/sgml/rules.sgml @@ -0,0 +1,28 @@ +<Chapter> +<Title>The <ProductName>Postgres</ProductName> Rule System</Title> + +<Para> + Production rule systems are conceptually simple, but + there are many subtle points involved in actually using + them. Consequently, we will not attempt to explain the + actual syntax and operation of the <ProductName>Postgres</ProductName> rule system + here. Instead, you should read +<XRef LinkEnd="STON90b" EndTerm="[STON90b]"> to understand + some of these points and the theoretical foundations of + the <ProductName>Postgres</ProductName> rule system before trying to use rules. + The discussion in this section is intended to provide + an overview of the <ProductName>Postgres</ProductName> rule system and point the + user at helpful references and examples. + + The "query rewrite" rule system modifies queries to + take rules into consideration, and then passes the modified + query to the query optimizer for execution. It + is very powerful, and can be used for many things such + as query language procedures, views, and versions. The + power of this rule system is discussed in +<XRef LinkEnd="ONG90" EndTerm="[ONG90]"> + as well as +<XRef LinkEnd="STON90b" EndTerm="[STON90b]">. +</Para> + +</Chapter> |