next release:

review tests to copy from hssqlppp

group by extensions. Question: some of the syntax can be represented
   by app and row ctor, should this be reused or new syntax created
   (the standard has special grammar for cube and rollup).

collate? -> postfix operator which binds very tightly:
a < 'foo' collate 'C'
->
Op "<" [Iden "a", SpecialOp "collate" [StringLit 'foo', StringLit
   'C']]
  also postfix in order by:
select a from t order by a collate 'C': add to order by syntax, one
   collation per column

much more table reference tests, for joins and aliases etc.

review internal sql collection for more syntax/tests

review syntax to replace maybe and bool with better ctors

----

add to website: pretty printed tpch, maybe other queries as
   demonstration
demo: convert tpch to sql server syntax exe processor

----

dialect framework
try to implement fixity without the hse hack
position annotation?
review abstract syntax (e.g. combine App with SpecialOp?)


----

Later general tasks:

more operators

sql server top syntax

named windows

extended string literals, escapes and other flavours (like pg and
   oracle custom delimiters)

run through other manuals for example queries and features: sql in a
   nutshell, sql guide, sql reference guide, sql standard, sql server
   manual, oracle manual, teradata manual + re-through postgresql
   manual and make notes in each case of all syntax and which isn't
   currently supported also.

check the order of exports, imports and functions/cases in the files
fix up the import namespaces/explicit names nicely

do some tests for parse errors?

left factor parsing code in remaining places

quasi quotes?

= sql support

proper character sets for identifiers, escapes, etc.

placeholder/positional arg

full number literals -> other bases?
apply, pivot
within group aggregate syntax

try to do full review of sql2003 query syntax

make ansi dialect which only supports ansi sql. Maybe there is a use
   for a separate SQL 92, 99 and 2003 dialects?

other dialect targets:
postgres
oracle
teradata
ms sql server
mysql?
db2?

maybe later: other dml
  insert, update, delete, truncate, merge + set, show?