大约有 44,000 项符合查询结果（耗时：0.0481秒） [XML]
Select distinct values from a table field
...tart with the fields in
distinct(), in the same order.
For example, SELECT DISTINCT ON (a) gives you the first row for each
value in column a. If you don’t specify an order, you’ll get some
arbitrary row.
If you want to e-g- extract a list of cities that you know shops in , the exam...
Difference between Select Unique and Select Distinct
...
SELECT UNIQUE is old syntax supported by Oracle's flavor of SQL. It is synonymous with SELECT DISTINCT.
Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than ...
How to select label for=“XYZ” in CSS?
...
The selector would be label[for=email], so in CSS:
label[for=email]
{
/* ...definitions here... */
}
...or in JavaScript using the DOM:
var element = document.querySelector("label[for=email]");
...or in JavaScript using...
Copy a file in a sane, safe and efficient way
...ing with the file system:
#include <copyfile.h>
int
copyfile(const char *from, const char *to, copyfile_state_t state, copyfile_flags_t flags);
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Understanding recursion [closed]
.... We'll use a binary tree of nodes, but this time the value held will be a character, not a number.
Our tree will have a special property, that for any node, its character comes after (in alphabetical order) the character held by its left child and before (in alphabetical order) the character held ...
Is it possible to specify condition in Count()?
...an use the fact that the count aggregate only counts the non-null values:
select count(case Position when 'Manager' then 1 else null end)
from ...
You can also use the sum aggregate in a similar way:
select sum(case Position when 'Manager' then 1 else 0 end)
from ...
...
How can I get column names from a table in Oracle?
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You can query the USER_TAB_COLUMNS table for table column metadata.
SELECT table_name, column_name, data_type, data_length
FROM USER_TAB_COLUMNS
WHERE table_name = 'MYTABLE'
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Import / Export database with SQL Server Server Management Studio
... if you want to also export the data, on the "Set Scripting Options" step, select the "Advanced" button and change "Types of data to script" from "Schema Only" to "Data Only" or "Schema and Data".
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Remove Last Comma from a string
...cript, how can I remove the last comma, but only if the comma is the last character or if there is only white space after the comma? This is my code.
I got a working fiddle . But it has a bug.
...
How to pattern match using regular expression in Scala?
... Some(p.Jo.StartsWith(fn)),
Some(p.`.*(\\w)$`.Regexp(lastChar))) =>
println(s"Match! $fn ...$lastChar")
case _ => println("nope")
}
}
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