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Select unique or distinct values from a list in UNIX shell script
I have a ksh script that returns a long list of values, newline separated, and I want to see only the unique/distinct values. It is possible to do this?
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Change auto increment starting number?
...foobar(moobar) values ("def");
INSERT INTO foobar(moobar) values ("xyz");
select * from foobar;
'10', 'abc'
'11', 'def'
'12', 'xyz'
This auto increments the id column by one starting at 10.
Auto increment in MySQL by 5, starting at 10:
drop table foobar
create table foobar(
id IN...
postgresql COUNT(DISTINCT …) very slow
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You can use this:
SELECT COUNT(*) FROM (SELECT DISTINCT column_name FROM table_name) AS temp;
This is much faster than:
COUNT(DISTINCT column_name)
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What is the difference between the remap, noremap, nnoremap and vnoremap mapping commands in Vim?
...f these sets of mappings, there is a mapping that works in normal, visual, select and operator modes (:map and :noremap), one that works in normal mode (:nmap and :nnoremap), one in visual mode (:vmap and :vnoremap) and so on.
For more guidance on this, see:
:help :map
:help :noremap
:help recursi...
How do I join two SQLite tables in my Android application?
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You need rawQuery method.
Example:
private final String MY_QUERY = "SELECT * FROM table_a a INNER JOIN table_b b ON a.id=b.other_id WHERE b.property_id=?";
db.rawQuery(MY_QUERY, new String[]{String.valueOf(propertyId)});
Use ? bindings instead of putting values into raw sql query.
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How to get the index of an item in a list in a single step?
...g different (e.g. on top of any IEnumerable<>).
Use the overload of Select which takes an index in the predicate, so you transform your list into an (index, value) pair:
var pair = myList.Select((Value, Index) => new { Value, Index })
.Single(p => p.Value.Prop == oProp...
IntelliJ - Convert a Java project/module into a Maven project/module
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Right-click on the module, select "Add framework support...", and check the "Maven" technology.
(This also creates a pom.xml for you to modify.)
If you mean adding source repository elements, I think you need to do that manually–not sure.
Pre-Inte...
How to sign an android apk file
...or Signing.
To create a signed and aligned .apk in
Eclipse:
Select the project in the Package Explorer and select File >
Export.
Open the Android folder, select Export Android Application, and click
Next.
The Export Android Application wizard now starts, which will guide...
What is the difference between the template method and the strategy patterns?
...atum); }
}
In summary:
Template method pattern: compile-time algorithm selection by subclassing
Strategy pattern: run-time algorithm selection by containment
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Use ASP.NET MVC validation with jquery ajax?
... where modelState[x].Errors.Count > 0
select new
{
key = x,
errors = modelState[x].Errors.
Select(y => y.ErrorMessage...