| $PostgreSQL: pgsql/src/backend/parser/README,v 1.10 2008/04/09 01:00:46 momjian Exp $ |
| |
| Parser |
| ====== |
| |
| This directory does more than tokenize and parse SQL queries. It also |
| creates Query structures for the various complex queries that are passed |
| to the optimizer and then executor. |
| |
| parser.c things start here |
| scan.l break query into tokens |
| scansup.c handle escapes in input strings |
| keywords.c turn keywords into specific tokens |
| gram.y parse the tokens and fill query-type-specific structures |
| analyze.c top level of parse analysis for optimizable queries |
| parse_clause.c handle clauses like WHERE, ORDER BY, GROUP BY, ... |
| parse_coerce.c handle coercing expressions to different data types |
| parse_expr.c handle expressions like col, col + 3, x = 3 or x = 4 |
| parse_oper.c handle operators in expressions |
| parse_agg.c handle aggregates, like SUM(col1), AVG(col2), ... |
| parse_func.c handle functions, table.column and column identifiers |
| parse_node.c create nodes for various structures |
| parse_target.c handle the result list of the query |
| parse_relation.c support routines for tables and column handling |
| parse_type.c support routines for data type handling |
| parse_utilcmd.c parse analysis for utility commands (done at execution time) |
