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postgres/src/backend/parser
Bruce Momjian bcaabc5698 Depending on my interpreting (and programming) skills, this might solve
anywhere from zero to two TODO items.

* Allow flag to control COPY input/output of NULLs

I got this:
COPY table .... [ WITH NULL AS 'string' ]
which does what you'd expect. The default is \N, otherwise you can use
empty strings, etc. On Copy In this acts like a filter: every data item
that looks like 'string' becomes a NULL. Pretty straightforward.

This also seems to be related to

* Make postgres user have a password by default

If I recall this discussion correctly, the problem was actually that the
default password for the postgres (or any) user is in fact "\N", because
of the way copy is used. With this change, the file pg_pwd is copied out
with nulls as empty strings, so if someone doesn't have a password, the
password is just '', which one would expect from a new account. I don't
think anyone really wants a hard-coded default password.

Peter Eisentraut                  Sernanders väg 10:115
1999-12-14 00:08:21 +00:00
..
1999-11-30 03:57:29 +00:00
1998-08-23 14:43:46 +00:00

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