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likewise increase the initial size of the scanner's literal buffer to 1024 (from 128). Instrumentation of the regression tests suggests that this saves a useful amount of repalloc() traffic --- the number of calls occurring during one set of tests drops from about 6900 to about 3900. The old sizes were chosen in the late 90's with an eye to machines much smaller than are common today.
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 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 type handling parse_utilcmd.c parse analysis for utility commands (done at execution time)