diff options
Diffstat (limited to 'trunk/src/examples/select_parser.py')
| -rw-r--r-- | trunk/src/examples/select_parser.py | 126 |
1 files changed, 0 insertions, 126 deletions
diff --git a/trunk/src/examples/select_parser.py b/trunk/src/examples/select_parser.py deleted file mode 100644 index da106ac..0000000 --- a/trunk/src/examples/select_parser.py +++ /dev/null @@ -1,126 +0,0 @@ -# select_parser.py
-# Copyright 2010, Paul McGuire
-#
-# a simple SELECT statement parser, taken from SQLite's SELECT statement
-# definition at http://www.sqlite.org/lang_select.html
-#
-from pyparsing import *
-ParserElement.enablePackrat()
-
-LPAR,RPAR,COMMA = map(Suppress,"(),")
-select_stmt = Forward().setName("select statement")
-
-# keywords
-(UNION, ALL, AND, INTERSECT, EXCEPT, COLLATE, ASC, DESC, ON, USING, NATURAL, INNER,
- CROSS, LEFT, OUTER, JOIN, AS, INDEXED, NOT, SELECT, DISTINCT, FROM, WHERE, GROUP, BY,
- HAVING, ORDER, BY, LIMIT, OFFSET, OR) = map(CaselessKeyword, """UNION, ALL, AND, INTERSECT,
- EXCEPT, COLLATE, ASC, DESC, ON, USING, NATURAL, INNER, CROSS, LEFT, OUTER, JOIN, AS, INDEXED, NOT, SELECT,
- DISTINCT, FROM, WHERE, GROUP, BY, HAVING, ORDER, BY, LIMIT, OFFSET, OR""".replace(",","").split())
-(CAST, ISNULL, NOTNULL, NULL, IS, BETWEEN, ELSE, END, CASE, WHEN, THEN, EXISTS,
- COLLATE, IN, LIKE, GLOB, REGEXP, MATCH, ESCAPE, CURRENT_TIME, CURRENT_DATE,
- CURRENT_TIMESTAMP) = map(CaselessKeyword, """CAST, ISNULL, NOTNULL, NULL, IS, BETWEEN, ELSE,
- END, CASE, WHEN, THEN, EXISTS, COLLATE, IN, LIKE, GLOB, REGEXP, MATCH, ESCAPE,
- CURRENT_TIME, CURRENT_DATE, CURRENT_TIMESTAMP""".replace(",","").split())
-keyword = MatchFirst((UNION, ALL, INTERSECT, EXCEPT, COLLATE, ASC, DESC, ON, USING, NATURAL, INNER,
- CROSS, LEFT, OUTER, JOIN, AS, INDEXED, NOT, SELECT, DISTINCT, FROM, WHERE, GROUP, BY,
- HAVING, ORDER, BY, LIMIT, OFFSET, CAST, ISNULL, NOTNULL, NULL, IS, BETWEEN, ELSE, END, CASE, WHEN, THEN, EXISTS,
- COLLATE, IN, LIKE, GLOB, REGEXP, MATCH, ESCAPE, CURRENT_TIME, CURRENT_DATE,
- CURRENT_TIMESTAMP))
-
-identifier = ~keyword + Word(alphas, alphanums+"_")
-collation_name = identifier.copy()
-column_name = identifier.copy()
-column_alias = identifier.copy()
-table_name = identifier.copy()
-table_alias = identifier.copy()
-index_name = identifier.copy()
-function_name = identifier.copy()
-parameter_name = identifier.copy()
-database_name = identifier.copy()
-
-# expression
-expr = Forward().setName("expression")
-
-integer = Regex(r"[+-]?\d+")
-numeric_literal = Regex(r"\d+(\.\d*)?([eE][+-]?\d+)?")
-string_literal = QuotedString("'")
-blob_literal = Regex(r"[xX]'[0-9A-Fa-f]+'")
-literal_value = ( numeric_literal | string_literal | blob_literal |
- NULL | CURRENT_TIME | CURRENT_DATE | CURRENT_TIMESTAMP )
-bind_parameter = (
- Word("?",nums) |
- Combine(oneOf(": @ $") + parameter_name)
- )
-type_name = oneOf("TEXT REAL INTEGER BLOB NULL")
-
-expr_term = (
- CAST + LPAR + expr + AS + type_name + RPAR |
- EXISTS + LPAR + select_stmt + RPAR |
- function_name.setName("function_name") + LPAR + Optional(delimitedList(expr)) + RPAR |
- literal_value |
- bind_parameter |
- Combine(identifier+('.'+identifier)*(0,2)).setName("ident")
- )
-
-UNARY,BINARY,TERNARY=1,2,3
-expr << infixNotation(expr_term,
- [
- (oneOf('- + ~') | NOT, UNARY, opAssoc.RIGHT),
- (ISNULL | NOTNULL | NOT + NULL, UNARY, opAssoc.LEFT),
- ('||', BINARY, opAssoc.LEFT),
- (oneOf('* / %'), BINARY, opAssoc.LEFT),
- (oneOf('+ -'), BINARY, opAssoc.LEFT),
- (oneOf('<< >> & |'), BINARY, opAssoc.LEFT),
- (oneOf('< <= > >='), BINARY, opAssoc.LEFT),
- (oneOf('= == != <>') | IS | IN | LIKE | GLOB | MATCH | REGEXP, BINARY, opAssoc.LEFT),
- ((BETWEEN,AND), TERNARY, opAssoc.LEFT),
- (IN + LPAR + Group(select_stmt | delimitedList(expr)) + RPAR, UNARY, opAssoc.LEFT),
- (AND, BINARY, opAssoc.LEFT),
- (OR, BINARY, opAssoc.LEFT),
- ])
-
-compound_operator = (UNION + Optional(ALL) | INTERSECT | EXCEPT)
-
-ordering_term = Group(expr('order_key') + Optional(COLLATE + collation_name('collate')) + Optional(ASC | DESC)('direction'))
-
-join_constraint = Group(Optional(ON + expr | USING + LPAR + Group(delimitedList(column_name)) + RPAR))
-
-join_op = COMMA | Group(Optional(NATURAL) + Optional(INNER | CROSS | LEFT + OUTER | LEFT | OUTER) + JOIN)
-
-join_source = Forward()
-single_source = ( (Group(database_name("database") + "." + table_name("table")) | table_name("table")) +
- Optional(Optional(AS) + table_alias("table_alias")) +
- Optional(INDEXED + BY + index_name("name") | NOT + INDEXED)("index") |
- (LPAR + select_stmt + RPAR + Optional(Optional(AS) + table_alias)) |
- (LPAR + join_source + RPAR) )
-
-join_source << (Group(single_source + OneOrMore(join_op + single_source + join_constraint)) |
- single_source)
-
-result_column = "*" | table_name + "." + "*" | Group(expr + Optional(Optional(AS) + column_alias))
-select_core = (SELECT + Optional(DISTINCT | ALL) + Group(delimitedList(result_column))("columns") +
- Optional(FROM + join_source("from")) +
- Optional(WHERE + expr("where_expr")) +
- Optional(GROUP + BY + Group(delimitedList(ordering_term)("group_by_terms")) +
- Optional(HAVING + expr("having_expr"))))
-
-select_stmt << (select_core + ZeroOrMore(compound_operator + select_core) +
- Optional(ORDER + BY + Group(delimitedList(ordering_term))("order_by_terms")) +
- Optional(LIMIT + (Group(expr + OFFSET + expr) | Group(expr + COMMA + expr) | expr)("limit")))
-
-tests = """\
- select * from xyzzy where z > 100
- select * from xyzzy where z > 100 order by zz
- select * from xyzzy
- select z.* from xyzzy
- select a, b from test_table where 1=1 and b='yes'
- select a, b from test_table where 1=1 and b in (select bb from foo)
- select z.a, b from test_table where 1=1 and b in (select bb from foo)
- select z.a, b from test_table where 1=1 and b in (select bb from foo) order by b,c desc,d
- select z.a, b from test_table left join test2_table where 1=1 and b in (select bb from foo)
- select a, db.table.b as BBB from db.table where 1=1 and BBB='yes'
- select a, db.table.b as BBB from test_table,db.table where 1=1 and BBB='yes'
- select a, db.table.b as BBB from test_table,db.table where 1=1 and BBB='yes' limit 50
- """
-
-select_stmt.runTests(tests)
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