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Is the NOLOCK (Sql Server hint) bad practice?
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With NOLOCK hint, the transaction isolation level for the SELECT statement is READ UNCOMMITTED. This means that the query may see dirty and inconsistent data.
This is not a good idea to apply as a rule. Even if this dirty read behavior is OK for your mission critical web based app...
Using str_replace so that it only acts on the first match?
...r downside is you have to use preg_quote() on the "needle" and escape meta-characters $ and \ in the replacement.
– Josh Davis
Aug 10 '09 at 2:53
32
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String concatenation vs. string substitution in Python
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did you make tests with real large strings (like 100000 chars)?
– drnk
Apr 29 '09 at 7:16
add a comment
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Postgres: SQL to list table foreign keys
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You can do this via the information_schema tables. For example:
SELECT
tc.table_schema,
tc.constraint_name,
tc.table_name,
kcu.column_name,
ccu.table_schema AS foreign_table_schema,
ccu.table_name AS foreign_table_name,
ccu.column_name AS foreign_column_nam...
Selecting multiple columns in a pandas dataframe
...7 44
R3 47 30 84
R4 41 62 1
R5 5 58 0
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Same works for selecting rows based on labels. Get the rows 'R6' to 'R10' from those columns:
df.loc['R6':'R10', 'C':'E']
Out:
C D E
R6 51 27 31
R7 83 19 18
R8 11 67 65
R9 78 27 29
R10 7 16 94
.loc also ac...
Direct vs. Delegated - jQuery .on()
...green").on(), binds a click handler directly to the span(s) that match the selector at the moment that code is executed. This means if other spans are added later (or have their class changed to match) they have missed out and will not have a click handler. It also means if you later remove the "gre...
Xcode source automatic formatting
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this shouldn't be selected as the answer. the answer below from @ken is correct
– Ryan Angilly
Feb 8 '13 at 16:44
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Extracting specific columns in numpy array
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I assume you wanted columns 1 and 9?
To select multiple columns at once, use
X = data[:, [1, 9]]
To select one at a time, use
x, y = data[:, 1], data[:, 9]
With names:
data[:, ['Column Name1','Column Name2']]
You can get the names from data.dtype.names…
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How do I change Eclipse to use spaces instead of tabs?
...dow » Preferences
Expand Web » HTML Files
Click Editor
Under Formatting, select the Indent using spaces radio button
Click OK to apply the changes.
CSS
Follow the same instructions for HTML, but select CSS Files instead of HTML Files.
JSP
By default, JSP files follow the formatting preference...
How to select last two characters of a string
I need to select last two characters from the variable, whether it is digit or letters.
9 Answers
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