@@ -25,33 +25,33 @@ <H2 ALIGN=CENTER>
2525The query is then identified as a < I > Utility</ I > query or a more complex
2626query. A < I > Utility</ I > query is processed by a query-specific function
2727in < A HREF ="../../backend/commands "> commands.</ A > A complex query, like
28- < CODE > SELECT, UPDATE,</ CODE > and
29- < CODE > DELETE</ CODE > requires much more handling.
28+ < I > SELECT, UPDATE,</ I > and
29+ < I > DELETE</ I > requires much more handling.
3030< P >
3131The parser takes a complex query, and creates a
3232< A HREF ="../../include/nodes/parsenodes.h "> Query</ A > structure that
3333contains all the elements used by complex queries. Query.qual holds the
34- < CODE > WHERE</ CODE > clause qualification, which is filled in by
34+ < I > WHERE</ I > clause qualification, which is filled in by
3535< A HREF ="../../backend/parser/parse_clause.c "> transformWhereClause().</ A >
3636Each table referenced in the query is represented by a < A
3737HREF ="../../include/nodes/parsenodes.h "> RangeTableEntry,</ A > and they
3838are linked together to form the < I > range table</ I > of the query, which is
3939generated by < A HREF ="../../backend/parser/parse_clause.c ">
4040makeRangeTable().</ A > Query.rtable holds the query's range table.
4141< P >
42- Certain queries, like < CODE > SELECT,</ CODE > return columns of data. Other
43- queries, like < CODE > INSERT</ CODE > and < CODE > UPDATE,</ CODE > specify the columns
42+ Certain queries, like < I > SELECT,</ I > return columns of data. Other
43+ queries, like < I > INSERT</ I > and < I > UPDATE,</ I > specify the columns
4444modified by the query. These column references are converted to < A
4545HREF ="../../include/nodes/primnodes.h "> Resdom</ A > entries, which are
4646linked together to make up the < I > target list</ I > of the query. The
4747target list is stored in Query.targetList, which is generated by
4848< A HREF ="../../backend/parser/parse_target.c "> transformTargetList().</ A >
4949< P >
50- Other query elements, like aggregates(< CODE > SUM()</ CODE > ), < CODE > GROUP BY,</ CODE >
51- and < CODE > ORDER BY</ CODE > are also stored in their own Query fields.
50+ Other query elements, like aggregates(< I > SUM()</ I > ), < I > GROUP BY,</ I >
51+ and < I > ORDER BY</ I > are also stored in their own Query fields.
5252< P >
53- The next step is for the Query to be modified by any < CODE > VIEWS</ CODE > or
54- < CODE > RULES</ CODE > that may apply to the query. This is performed by the < A
53+ The next step is for the Query to be modified by any < I > VIEWS</ I > or
54+ < I > RULES</ I > that may apply to the query. This is performed by the < A
5555HREF ="../../backend/rewrite "> rewrite</ A > system.
5656< P >
5757The < A HREF ="../../backend/optimizer "> optimizer</ A > takes the Query
@@ -60,7 +60,7 @@ <H2 ALIGN=CENTER>
6060operations to be performed to execute the query. The < A
6161HREF ="../../backend/optimizer/path "> path</ A > module determines the best
6262table join order and join type of each table in the RangeTable, using
63- Query.qual(< CODE > WHERE</ CODE > clause) to consider optimal index usage.
63+ Query.qual(< I > WHERE</ I > clause) to consider optimal index usage.
6464< P >
6565The Plan is then passed to the < A
6666HREF ="../../backend/executor "> executor</ A > for execution, and the result
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