TESTS TO ADD

* CACHE-TABLE-QUERIES
* Test that ":db-kind :key" adds an index for that key. This is complicated by different
  backends showing autogenerated primary key in different ways.
* Large object testing
* Test bigint type
* :db-constraint tests
* test *db-auto-sync* 
* test SELECT caching
* for-each-row macro
* universal-time 

COMMONSQL SPEC

* Incompatible 

 >> The functional sql interface 
  
    SELECT 
      o keyword arg :refresh should function as advertised 

 >> Symbolic SQL syntax 

      o Complete sql expressions (see operations.lisp)

         nvl (Oracle specific) 
         userenv (Oracle specific) 
	 minus (Oracle specific: does the same as EXCEPT) 

      o variables (e.g., table identifiers) should be instantiated at runtime 


VARIANCES FROM COMMONSQL

UPDATE-OBJECT-JOINS:
 Rather than simply reading the values for each
 object, to meet CommonSQL spec need to generate a single
 query to read values for all objects, up to max-len count.

OPTIMIZATIONS
 
* Revisit result-type list creation,perhaps caching

POSSIBLE EXTENSIONS

* port Oracle backend to UFFI
* large object support 
* add support for prepared statements


NOTES ABOUT THE BACKENDS

MYSQL 

drop-index:   requires a table to be specified with the :from keyword parameter
views:        mysql does not support views  
queries:      nested subqueries are not supported
syntax:       doesn't support the sql concatenation operator (||). 

SQLITE 

create-view:  column-list parameter not supported 
syntax:       doesn't support the sql SUBSTRING operator.