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optimizer rather than parser. This has many advantages, such as not getting fooled by chance uses of operator names ~ and ~~ (the operators are identified by OID now), and not creating useless comparison operations in contexts where the comparisons will not actually be used as indexquals. The new code also recognizes exact-match LIKE and regex patterns, and produces an = indexqual instead of >= and <=. This change does NOT fix the problem with non-ASCII locales: the code still doesn't know how to generate an upper bound indexqual for non-ASCII collation order. But it's no worse than before, just the same deficiency in a different place... Also, dike out loc_restrictinfo fields in Plan nodes. These were doing nothing useful in the absence of 'expensive functions' optimization, and they took a considerable amount of processing to fill in. |
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.. | ||
.cvsignore | ||
analyze.c | ||
gram.y | ||
keywords.c | ||
Makefile | ||
parse_agg.c | ||
parse_clause.c | ||
parse_coerce.c | ||
parse_expr.c | ||
parse_func.c | ||
parse_node.c | ||
parse_oper.c | ||
parse_relation.c | ||
parse_target.c | ||
parse_type.c | ||
parser.c | ||
README | ||
scan.l | ||
scansup.c |
This directory does more than tokenize and parse SQL queries. It also creates Query structures for the various complex queries that is passed to the optimizer and then executor. parser.c things start here scan.l break query into tokens scansup.c handle escapes in input keywords.c turn keywords into specific tokens gram.y parse the tokens and fill query-type-specific structures analyze.c handle post-parse processing for each query type parse_clause.c handle clauses like WHERE, ORDER BY, GROUP BY, ... parse_coerce.c used for coercing expressions of different types parse_expr.c handle expressions like col, col + 3, x = 3 or x = 4 parse_oper.c handle operations 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