Figure \ref{parsetree} shows the parse tree built by the
grammar rules and actions given in gram.y for the query
- given in endterm="simple-select">
+ given in
(without the operator tree for
the where clause which is shown in figure \ref{where_clause}
because there was not enough space to show both data structures in one
Figure \ref{where_clause} shows the operator tree built for the
- where clause of the SQL query given in example
- endterm="simple-select">
+ where clause of the SQL query given in
+
which is attached to the field
qual of the SelectStmt node. The top node of the
operator tree is an A_Expr node representing an AND
within a cluster make calls to the library.
The library sends user requests over the network to the
-( EndTerm="PGARCH-CONNECTIONS">(a)),
+((a)),
which in turn starts a new backend server process
-( EndTerm="PGARCH-CONNECTIONS">(b))
+((b))
How a connection is established
and connects the frontend process to the new server
-( EndTerm="PGARCH-CONNECTIONS">(c)).
+((c)).
From that point on, the frontend process and the backend
server communicate without intervention by the
postmaster. Hence, the
postmaster is always running, waiting
applications that wish to access a given database
within a cluster make calls to the library.
The library sends user requests over the network to the
-
postmaster (
EndTerm="ARCH-CLIENTSERVER">),
which in turn starts a new backend server process
The Reference Manual gives a more detailed explanation
of these catalogs and their attributes. However,
- endterm="EXTEND-CATALOGS" linkend="EXTEND-CATALOGS">
+
shows the major entities and their relationships
in the system catalogs. (Attributes that do not refer
to other entities are not shown unless they are part of
-
libpq - C++ Binding Library
+
libpq++ - C++ Binding Library
libpq++ is the C++ API to
an application program:
- Refer to the linkend="libpq-envars"> for a complete
+ Refer to linkend="libpq-envars"> for a complete
list of available connection options.
There are currently three procedural languages available in the standard
Postgres distribution (PLSQL, PLTCL and
PLPERL), and other languages can be defined.
- Refer to -title" endterm="xplang-title"> for
+ Refer to for
more information.
it can be dynamically loaded into
always requires special flags.
- See -title" endterm="dfunc-title">
+ See
for a detailed explanation of how to do it for
your particular operating system.
Look back at
- endterm="EXTEND-CATALOGS" linkend="EXTEND-CATALOGS">.
+ .
The right half shows the catalogs that we must modify in order to tell
Postgres how to use a user-defined type and/or
user-defined operators with an index (i.e., pg_am, pg_amop,