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“Undefined reference to” template class constructor [duplicate]
...e in order to ensure this problem never happens! (cola<int>, cola<char>, cola<ostream>, cola< cola<int> > ... and so on ...)
The two answers are:
Tell the compiler, at the end of cola.cpp, which particular template classes will be required, forcing it to compile cola...
select count(*) from table of mysql in php
...s keyword in order to call it from mysql_fetch_assoc
$result=mysql_query("SELECT count(*) as total from Students");
$data=mysql_fetch_assoc($result);
echo $data['total'];
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No visible cause for “Unexpected token ILLEGAL”
...e error is raised if, for example, you try to run a js file with a rogue @ character, a misplaced curly brace, bracket, "smart quotes", single quotes not enclosed properly (e.g. this.run('dev1)) and so on.
A lot of different situations can cause this error. But if you don't have any obvious syntax ...
How do I delete multiple rows in Entity Framework (without foreach)
...Expression<Func<T, bool>> filter) where T : class
{
string selectSql = db.Set<T>().Where(filter).ToString();
string fromWhere = selectSql.Substring(selectSql.IndexOf("FROM"));
string deleteSql = "DELETE [Extent1] " + fromWhere;
db.Database.ExecuteSqlCommand(deleteSq...
Which rows are returned when using LIMIT with OFFSET in MySQL?
...
OFFSET is nothing but a keyword to indicate starting cursor in table
SELECT column FROM table LIMIT 18 OFFSET 8 -- fetch 18 records, begin with record 9 (OFFSET 8)
you would get the same result form
SELECT column FROM table LIMIT 8, 18
visual representation (R is one record in the table i...
Git Bash doesn't see my PATH
...
While you are installing Git, you can select the option shown below, it'll help you to set the path automatically.
Its worked out for me :)
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Importing CommonCrypto in a Swift framework
...code.app path which can vary system-to-system, especially if you use xcode-select to switch to a beta version, or are building on a CI server where multiple versions are installed in non-standard locations. You also don't need to hard code the SDK so this should work for iOS, macOS, etc. You also do...
Extract value of attribute node via XPath
...ou ignore the Parent node altogether and use:
//child/@name
you can select name attribute of all child nodes in one go.
name="Child_2"
name="Child_4"
name="Child_1"
name="Child_3"
name="Child_1"
name="Child_2"
name="Child_4"
name="Child_3"
...
Can PostgreSQL index array columns?
... for this test...
SET enable_seqscan TO off;
EXPLAIN ANALYZE
SELECT * FROM "Test" WHERE "Column1" @> ARRAY[20];
Result:
Bitmap Heap Scan on "Test" (cost=4.26..8.27 rows=1 width=32) (actual time=0.014..0.015 rows=2 loops=1)
Recheck Cond: ("Column1" @> '{20}'::integer[])
-&...
what is reverse() in Django
... question = get_object_or_404(Question, pk=question_id)
try:
selected = question.choice_set.get(pk=request.POST['choice'])
except KeyError:
# handle exception
pass
else:
selected.votes += 1
selected.save()
return HttpResponseRedirect(reve...