# this was used for debugging null productions (a nearly full sql grammar
# is available on request).
#set this to automatically rebuild the grammar.
REBUILD = 1
MARSHALFILE = "SQLTEST.mar"
SELECTRULES = """
## highest level for select statement (not select for update)
select-statement ::
@R selectR :: select-statement >>
SELECT
from-clause
where-clause
group-by-clause
having-clause
## generalized to allow null from clause eg: select 2+2
@R fromNull :: from-clause >>
@R fromFull :: from-clause >> FROM
@R whereNull :: where-clause >>
@R whereFull :: where-clause >> WHERE
@R groupNull :: group-by-clause >>
@R groupFull :: group-by-clause >> GROUP BY
@R havingNull :: having-clause >>
@R havingFull :: having-clause >> HAVING
@R unionNull :: union-clause >>
@R unionFull :: union-clause >> UNION
"""
SELECTNONTERMS = """
select-statement
all-distinct select-list table-reference-list
where-clause group-by-clause having-clause union-clause
maybe-order-by
search-condition column-list maybe-all order-by-clause
column-name from-clause
"""
# of these the following need resolution
# (select-list) (table-reference-list)
# (search-condition) order-by-clause (column-name)
SELECTKEYWORDS = """
SELECT FROM WHERE GROUP BY HAVING UNION DISTINCT ALL AS
"""
# test generation of the grammar
def BuildSQLG():
import kjParseBuild
SQLG = kjParseBuild.NullCGrammar()
SQLG.SetCaseSensitivity(0)
SQLG.Keywords(SELECTKEYWORDS)
SQLG.Nonterms(SELECTNONTERMS)
# no comments yet
SQLG.Declarerules(SELECTRULES)
print "building"
SQLG.Compile()
print "marshaling"
outfile = open( MARSHALFILE, "w")
SQLG.MarshalDump(outfile)
outfile.close()
return SQLG
# load function
def LoadSQLG():
import kjParser
print "unmarshalling"
infile = open(MARSHALFILE, "r")
SQLG = kjParser.UnMarshalGram(infile)
infile.close()
return SQLG
#### for testing
if REBUILD:
SQLG0 = BuildSQLG()
print " rebuilt SQLG0 as compilable grammar"
SQLG = LoadSQLG()
print " build SQLG as reloaded grammar"
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