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How to do a regular expression replace in MySQL?
...ositions and perform substring substitution and extraction, respectively.
SELECT REGEXP_REPLACE('Stackoverflow','[A-Zf]','-',1,0,'c');
-- Output:
-tackover-low
DBFiddle Demo
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best way to add license section to iOS settings bundle
...save it to the root of your project.
Expand the Settings.bundle group and select Root.plist. You will need to add a new section where its key will be Preference Items of type Array. Add the following information:
The Filename key points to the plist that was created by this script. You can cha...
Using psql how do I list extensions installed in a database?
...org/docs/current/static/app-psql.html
Doing it in plain SQL it would be a select on pg_extension:
SELECT *
FROM pg_extension
http://www.postgresql.org/docs/current/static/catalog-pg-extension.html
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getting type T from IEnumerable
... t.GetGenericTypeDefinition() == typeof(IEnumerable<>))
.Select(t => t.GetGenericArguments()[0]);
}
Some objects implement more than one generic IEnumerable so it is necessary to return an enumeration of them.
Edit: Although, I have to say, it's a terrible idea for a class to...
Get selected value of a dropdown's item using jQuery
How can I get the selected value of a dropdown box using jQuery?
I tried using
30 Answers
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SQL is null and = null [duplicate]
...e t (x int, y int);
insert into t values (null, null), (null, 1), (1, 1);
select 'x = null' as test , x, y from t where x = null
union all
select 'x != null', x, y from t where x != null
union all
select 'not (x = null)', x, y from t where not (x = null)
union all
select 'x = y', x, y from t where ...
configure: error: C compiler cannot create executables
...'ve installed Xcode 4.3.x, you need to launch it, go into its preferences, select the Downloads tab, and click "Install" next to the Command Line Tools package.
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How to write UPDATE SQL with Table alias in SQL Server 2008?
... Mark Byers - Great Answer!! This syntax allows me to add a commented out Select statement, which allows me to test the update by doing the select first (highlight from the select down and execute): SET Q.TITLE = 'TEST' -- SELECT *
– user1636464
Aug 30 '12 at ...
How to delete a row by reference in data.table?
...el.idxs' vs. 'keep.idxs'
keep.idxs <- setdiff(DT[, .I], del.idxs); # select row indexes to keep
cols = names(DT);
DT.subset <- data.table(DT[[1]][keep.idxs]); # this is the subsetted table
setnames(DT.subset, cols[1]);
for (col in cols[2:length(cols)]) {
DT.subset[, (col) := DT[...
What's the difference between MyISAM and InnoDB? [duplicate]
... on the table, and while that lock is held, no other session can perform a SELECT or a DML operation on the table.
Those two specific engines you asked about (InnoDB and MyISAM) have different design goals. MySQL also has other storage engines, with their own design goals.
So, in choosing between In...