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
|
"""
Take a table with a primary key and some nullable text fields.
Strip leading spaces in all text fields and
replace the fields which are all blanks with None.
usage:
$ python %s <db-uri> <table>
"""
import os, sys
from sqlplain import connect, util
from sqlplain.table import KTable
def strip(value):
"value is None or a string"
if value is None: # do nothing
return None
return value.strip() or None
def get_text_fields(conn, table, exclude=()):
'Returns the text fields of a table, possibly excluding some of them'
names = []
for row in util.get_descr(conn, table):
if row.type_code == 1 and row.name not in exclude:
names.append(row.name)
return names
def replace_blanks(conn, tablename):
# conn.chatty = True
pkeys = util.get_kfields(conn, tablename)
textfields = get_text_fields(conn, tablename, exclude=pkeys)
tbl = KTable.type(tablename, pkeys, textfields)(conn)
for row in tbl.select():
kw = dict((tf, strip(getattr(row, tf))) for tf in textfields)
newrow = row._replace(**kw)
if newrow != row:
tbl.update_row(newrow)
print newrow
else:
sys.stdout.write('.')
sys.stdout.flush()
if __name__ == '__main__':
try:
uri, tablename = sys.argv[1:]
except ValueError:
sys.exit(__doc__ % sys.argv[0])
replace_blanks(connect(uri), tablename)
|
