FilesExpand file tree

 master

/

extract_table_names.py

Copy path

Blame

More file actions

Blame

More file actions

Latest commit

 

History

History

History

70 lines (58 loc) · 2.07 KB

 master

/

extract_table_names.py

Copy path

Top

File metadata and controls

• Code
• Blame

70 lines (58 loc) · 2.07 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

#!/usr/bin/env python

# -*- coding: utf-8 -*-

#

# Copyright (C) 2009-2018 the sqlparse authors and contributors

# <see AUTHORS file>

#

# This example is part of python-sqlparse and is released under

# the BSD License: https://opensource.org/licenses/BSD-3-Clause

#

# This example illustrates how to extract table names from nested

# SELECT statements.

#

# See:

# https://groups.google.com/forum/#!forum/sqlparse/browse_thread/thread/b0bd9a022e9d4895

import sqlparse

from sqlparse.sql import IdentifierList, Identifier

from sqlparse.tokens import Keyword, DML

def is_subselect(parsed):

if not parsed.is_group:

return False

for item in parsed.tokens:

if item.ttype is DML and item.value.upper() == 'SELECT':

return True

return False

def extract_from_part(parsed):

from_seen = False

for item in parsed.tokens:

if from_seen:

if is_subselect(item):

for x in extract_from_part(item):

yield x

elif item.ttype is Keyword:

raise StopIteration

else:

yield item

elif item.ttype is Keyword and item.value.upper() == 'FROM':

from_seen = True

def extract_table_identifiers(token_stream):

for item in token_stream:

if isinstance(item, IdentifierList):

for identifier in item.get_identifiers():

yield identifier.get_name()

elif isinstance(item, Identifier):

yield item.get_name()

# It's a bug to check for Keyword here, but in the example

# above some tables names are identified as keywords...

elif item.ttype is Keyword:

yield item.value

def extract_tables(sql):

stream = extract_from_part(sqlparse.parse(sql)[0])

return list(extract_table_identifiers(stream))

if __name__ == '__main__':

sql = """

select K.a,K.b from (select H.b from (select G.c from (select F.d from

(select E.e from A, B, C, D, E), F), G), H), I, J, K order by 1,2;

"""

tables = ', '.join(extract_tables(sql))

print('Tables: {0}'.format(tables))