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+# simpleSQL.py
+#
+# simple demo of using the parsing library to do simple-minded SQL parsing
+# could be extended to include where clauses etc.
+#
+# Copyright (c) 2003,2016, Paul McGuire
+#
+from pyparsing import Literal, CaselessLiteral, Word, delimitedList, Optional, \
+    Combine, Group, alphas, nums, alphanums, ParseException, Forward, oneOf, quotedString, \
+    ZeroOrMore, restOfLine, Keyword, upcaseTokens
+
+# define SQL tokens
+selectStmt = Forward()
+SELECT = Keyword("select", caseless=True)
+FROM = Keyword("from", caseless=True)
+WHERE = Keyword("where", caseless=True)
+
+ident          = Word( alphas, alphanums + "_$" ).setName("identifier")
+columnName     = ( delimitedList( ident, ".", combine=True ) ).addParseAction(upcaseTokens)
+columnNameList = Group( delimitedList( columnName ) )
+tableName      = ( delimitedList( ident, ".", combine=True ) ).addParseAction(upcaseTokens)
+tableNameList  = Group( delimitedList( tableName ) )
+
+whereExpression = Forward()
+and_ = Keyword("and", caseless=True)
+or_ = Keyword("or", caseless=True)
+in_ = Keyword("in", caseless=True)
+
+E = CaselessLiteral("E")
+binop = oneOf("= != < > >= <= eq ne lt le gt ge", caseless=True)
+arithSign = Word("+-",exact=1)
+realNum = Combine( Optional(arithSign) + ( Word( nums ) + "." + Optional( Word(nums) )  |
+                                                         ( "." + Word(nums) ) ) + 
+            Optional( E + Optional(arithSign) + Word(nums) ) )
+intNum = Combine( Optional(arithSign) + Word( nums ) + 
+            Optional( E + Optional("+") + Word(nums) ) )
+
+columnRval = realNum | intNum | quotedString | columnName # need to add support for alg expressions
+whereCondition = Group(
+    ( columnName + binop + columnRval ) |
+    ( columnName + in_ + "(" + delimitedList( columnRval ) + ")" ) |
+    ( columnName + in_ + "(" + selectStmt + ")" ) |
+    ( "(" + whereExpression + ")" )
+    )
+whereExpression << whereCondition + ZeroOrMore( ( and_ | or_ ) + whereExpression ) 
+
+# define the grammar
+selectStmt <<= (SELECT + ('*' | columnNameList)("columns") + 
+                FROM + tableNameList( "tables" ) + 
+                Optional(Group(WHERE + whereExpression), "")("where"))
+
+simpleSQL = selectStmt
+
+# define Oracle comment format, and ignore them
+oracleSqlComment = "--" + restOfLine
+simpleSQL.ignore( oracleSqlComment )
+
+if __name__ == "__main__":
+	simpleSQL.runTests("""\
+	    SELECT * from XYZZY, ABC
+	    select * from SYS.XYZZY
+	    Select A from Sys.dual
+	    Select A,B,C from Sys.dual
+	    Select A, B, C from Sys.dual
+	    Select A, B, C from Sys.dual, Table2   
+	    Xelect A, B, C from Sys.dual
+	    Select A, B, C frox Sys.dual
+	    Select
+	    Select &&& frox Sys.dual
+	    Select A from Sys.dual where a in ('RED','GREEN','BLUE')
+	    Select A from Sys.dual where a in ('RED','GREEN','BLUE') and b in (10,20,30)
+	    Select A,b from table1,table2 where table1.id eq table2.id -- test out comparison operators""")