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Setting up foreign keys in phpMyAdmin?
...ting up a database using phpMyAdmin. I have two tables ( foo and bar ), indexed on their primary keys . I am trying to create a relational table ( foo_bar ) between them, using their primary keys as foreign keys.
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How to remove constraints from my MySQL table?
...rrect, because simply removing the foreign key will not remove the related index. Of course the index may have been created separately, but if it was created as a consequence of adding the foreign key in the first place, then it will not be removed simply by dropping the foreign key.
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How to get the caller's method name in the called method?
... in findsource if not sourcefile and file[0] + file[-1] != '<>': IndexError: string index out of range Can u please provide suggestion. Thanx in advance.
– Pooja
Aug 13 '14 at 11:07
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Conditional Replace Pandas
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.ix indexer works okay for pandas version prior to 0.20.0, but since pandas 0.20.0, the .ix indexer is deprecated, so you should avoid using it. Instead, you can use .loc or iloc indexers. You can solve this problem by:
mask = d...
Selecting the last value of a column
... answer, but we can tidy it up by just specifying the full column range:
=INDEX(G2:G, COUNT(G2:G))
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Add Foreign Key to existing table
...150/
On the top of my head two things come to mind.
Is your foreign key index a unique name in the whole database (#3 in the list)?
Are you trying to set the table PK to NULL on update (#5 in the list)?
I'm guessing the problem is with the set NULL on update (if my brains aren't on backwards to...
Python loop counter in a for loop [duplicate]
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Use enumerate() like so:
def draw_menu(options, selected_index):
for counter, option in enumerate(options):
if counter == selected_index:
print " [*] %s" % option
else:
print " [ ] %s" % option
options = ['Option 0', 'Option 1', 'Opt...
How to read a .xlsx file using the pandas Library in iPython?
...xcel:
read_excel(io, sheetname=0, header=0, skiprows=None, skip_footer=0, index_col=None, names=None, parse_cols=None, parse_dates=False, date_parser=None, na_values=None, thousands=None, convert_float=True, has_index_names=None, converters=None, true_values=None, false_values=None, engine=None, sq...
What does the KEY keyword mean?
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Quoting from http://dev.mysql.com/doc/refman/5.1/en/create-table.html
{INDEX|KEY}
So KEY is an INDEX ;)
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Create unique constraint with null columns
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Create two partial indexes:
CREATE UNIQUE INDEX favo_3col_uni_idx ON favorites (user_id, menu_id, recipe_id)
WHERE menu_id IS NOT NULL;
CREATE UNIQUE INDEX favo_2col_uni_idx ON favorites (user_id, recipe_id)
WHERE menu_id IS NULL;
This way,...