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MySQL LIKE IN()?
...eing sufficient to give me the correct results, using LIKE as well allowed MySQL to reduce the result set considerably before having to use the slower REGEXP criteria.
– mpen
Feb 15 '12 at 0:11
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Tactics for using PHP in a high-load site
...l you measure and compare your changes.
For example, for many years, the MySQL query cache was the solution to all of our performance problems. If your site was slow, MySQL experts suggested turning the query cache on. It turns out that if you have a high write load, the cache is actually cripplin...
Does MySQL ignore null values on unique constraints?
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Yes, MySQL allows multiple NULLs in a column with a unique constraint.
CREATE TABLE table1 (x INT NULL UNIQUE);
INSERT table1 VALUES (1);
INSERT table1 VALUES (1); -- Duplicate entry '1' for key 'x'
INSERT table1 VALUES (NULL);...
How do I show the schema of a table in a MySQL database?
From the MySQL console, what command displays the schema of any given table?
5 Answers
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How do I check if a column is empty or null in MySQL?
...OR some_col = ' ' (one space inserted in the string) then it works on both MySQL and Oracle, see answer of "onedaywhen". some_col = '' doesn't work on Oracle as empty strings mean NULL there.
– Johanna
May 18 '15 at 14:07
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Python os.path.join on Windows
...join('c:', os.sep, 'sourcedir')
Since you also need os.sep for the posix root path:
mypath = os.path.join(os.sep, 'usr', 'lib')
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How to delete from multiple tables in MySQL?
...h out to an EXISTS in 99% of the cases and then there is the 1% where this MySQL syntax takes the day.
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MySQL ON vs USING?
In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...
What's the difference between VARCHAR and CHAR?
What's the difference between VARCHAR and CHAR in MySQL?
14 Answers
14
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How do I list all files of a directory?
... os
# Getting the current work directory (cwd)
thisdir = os.getcwd()
# r=root, d=directories, f = files
for r, d, f in os.walk(thisdir):
for file in f:
if file.endswith(".docx"):
print(os.path.join(r, file))
os.listdir(): get files in the current directory (Python 2)
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