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Can't use method return value in write context
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This is a much better answer than the one currently selected.
– SystemParadox
Sep 9 '11 at 14:20
20
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Do I need to create indexes on foreign keys on Oracle?
...ance of an index may be unacceptable.
Most salient here would seem to be selectivity: if the values in the index would be highly duplicated then it may give better performance to drop the index (if possible) and allow a table scan.
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How do I restore a dump file from mysqldump?
... following these steps…
Open MySQL Administrator and connect to server
Select "Catalogs" on the left
Right click in the lower-left box and choose "Create New Schema"
MySQL Administrator http://img204.imageshack.us/img204/7528/adminsx9.th.gif enlarge image
Name the new schema (example: "dbn")
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How do I remove a file from the FileList
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If you want to delete only several of the selected files: you can't. The File API Working Draft you linked to contains a note:
The HTMLInputElement interface
[HTML5] has a readonly FileList
attribute, […]
[emphasis mine]
Reading a bit of the HTML 5 Work...
Debugging sqlite database on the device
...ed a database with two tables and a dozen or so rows in each, and did full select queries on each table. One worked fine, the other reported a data error in the file. My best guess right now is an encoding mismatch between the Android and local shell.
– Mason
F...
How to write a simple database engine [closed]
...h pattern of delimiter is never used in your data itself. i.e. if you have selected <*> for example to separate columns, you should validate the data you are placing in this table not to contain this pattern. you could also use a row header and a column header by specifying size of row and som...
How to theme the ENTIRE Xcode IDE to light-on-dark?
...ground by going into preferences ⌘., then go to Fonts & Colors, then select the Console. Now you can edit its background:
Just be sure to edit the font colors of the various input and outputs texts if you choose black. By default all of the input/output fonts are black, only the console pro...
Using .gitignore to ignore everything but specific directories
...at I have a bunch of WordPress websites in my git repo, of which I want to selectively commit only the content of my themes folders, while ignoring the rest of the redundant files found in WordPress.
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pull out p-values and r-squared from a linear regression
... need. The beta, se, t and p vectors are stored in it. Get the p-values by selecting the 4th column of the coefficients matrix (stored in the summary object):
summary(fit)$coefficients[,4]
summary(fit)$r.squared
Try str(summary(fit)) to see all the info that this object contains.
Edit: I had ...
MySQL how to join tables on two fields
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SELECT *
FROM t1
JOIN t2 USING (id, date)
perhaps you'll need to use INNEER JOIN or
where t2.id is not null
if you want results only matching both conditions
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