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insert a NOT NULL column to an existing table
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As an option you can initially create Null-able column, then update your table column with valid not null values and finally ALTER column to set NOT NULL constraint:
ALTER TABLE MY_TABLE ADD STAGE INT NULL
GO
UPDATE MY_TABLE SET <a valid not null values for your column>
GO
ALTER TABLE MY_TA...
Why are joins bad when considering scalability?
...ted comparison for a join is now much smaller and potentially pre-indexed.
Table partitions (helps with large data sets by spreading the load out to multiple disks, or limiting what might have been a table scan down to a partition scan)
OLAP (pre-computes results of certain kinds of queries/joins. I...
What are database normal forms and can you give examples? [closed]
...y normalization, which is a process of organizing columns (attributes) and tables (relations) to reduce data redundancy and improve data integrity. (as written on Wikipedia ).
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Copy table without copying data
copies the table foo and duplicates it as a new table called bar .
4 Answers
4
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How do I do base64 encoding on iOS?
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#import "NSStringAdditions.h"
static char base64EncodingTable[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', ...
What's the easiest way to escape HTML in Python?
...with all non-ascii unicode chars encoded using the xml character reference table.
– nosklo
Jun 23 '10 at 3:48
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What is the correct way to document a **kwargs parameter?
...t call out kwargs specifically. (other_silly_variable=None)
def fetch_bigtable_rows(big_table, keys, other_silly_variable=None):
"""Fetches rows from a Bigtable.
Retrieves rows pertaining to the given keys from the Table instance
represented by big_table. Silly things may happen if
other_silly_v...
How to dump a table to console?
I'm having trouble displaying the contents of a table which contains nested tables (n-deep). I'd like to just dump it to std out or the console via a print statement or something quick and dirty but I can't figure out how. I'm looking for the rough equivalent that I'd get when printing an NSDicti...
How to prevent gcc optimizing some statements in C?
In order to make a page dirty (switching on the dirty bit in the page table entry), I touch the first bytes of the page like this:
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How to limit the maximum value of a numeric field in a Django model?
...t the validation in a form. The question of which range of numbers is acceptable is as much a part of the model as is the question of which kind of number is acceptable. I don't want to have to tell every form through which the model is editable, just which range of numbers to accept. This would vi...