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This commit switches query jumbling so as prepared statement names are treated as constants in DeallocateStmt. A boolean field is added to DeallocateStmt to make a distinction between ALL and named prepared statements, as "name" was used to make this difference before, NULL meaning DEALLOCATE ALL. Prior to this commit, DEALLOCATE was not tracked in pg_stat_statements, for the reason that it was not possible to treat its name parameter as a constant. Now that query jumbling applies to all the utility nodes, this reason does not apply anymore. Like 638d42a3c520, this can be a huge advantage for monitoring where prepared statement names are randomly generated, preventing bloat in pg_stat_statements. A couple of tests are added to track the new behavior. Author: Dagfinn Ilmari Mannsåker, Michael Paquier Reviewed-by: Julien Rouhaud Discussion: https://postgr.es/m/ZMhT9kNtJJsHw6jK@paquier.xyz
src/backend/parser/README 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 gram.y parse the tokens and produce a "raw" parse tree analyze.c top level of parse analysis for optimizable queries parse_agg.c handle aggregates, like SUM(col1), AVG(col2), ... parse_clause.c handle clauses like WHERE, ORDER BY, GROUP BY, ... parse_coerce.c handle coercing expressions to different data types parse_collate.c assign collation information in completed expressions parse_cte.c handle Common Table Expressions (WITH clauses) parse_expr.c handle expressions like col, col + 3, x = 3 or x = 4 parse_enr.c handle ephemeral named rels (trigger transition tables, ...) parse_func.c handle functions, table.column and column identifiers parse_merge.c handle MERGE parse_node.c create nodes for various structures parse_oper.c handle operators in expressions parse_param.c handle Params (for the cases used in the core backend) parse_relation.c support routines for tables and column handling parse_target.c handle the result list of the query parse_type.c support routines for data type handling parse_utilcmd.c parse analysis for utility commands (done at execution time) See also src/common/keywords.c, which contains the table of standard keywords and the keyword lookup function. We separated that out because various frontend code wants to use it too.