大约有 43,000 项符合查询结果（耗时：0.0303秒） [XML]
std::wstring VS std::string
...s between std::string and std::wstring . I know wstring supports wide characters such as Unicode characters. I have got the following questions:
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Why unsigned integer is not available in PostgreSQL?
...< 65536);
Here is what psql gives when I try to abuse the type.
DS1=# select (346346 :: uint2);
ERROR: value for domain uint2 violates check constraint "uint2_check"
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Apply formula to the entire column
...olumn B as the image from the OP. For me, It simply fills the value of the selected cell.
– Assimilater
Aug 4 '15 at 23:04
11
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Get string character by index - Java
I know how to work out the index of a certain character or number in a string, but is there any predefined method I can use to give me the character at the nth position? So in the string "foo", if I asked for the character with index 0 it would return "f".
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How to change the CHARACTER SET (and COLLATION) throughout a database?
...re schema to utf8. Hope this helps!
-- Change DATABASE Default Collation
SELECT DISTINCT concat('ALTER DATABASE `', TABLE_SCHEMA, '` CHARACTER SET utf8 COLLATE utf8_unicode_ci;')
from information_schema.tables
where TABLE_SCHEMA like 'database_name';
-- Change TABLE Collation / Char Set
SELECT...
How to convert a char array back to a string?
I have a char array:
15 Answers
15
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LISTAGG in Oracle to return distinct values
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19c and later:
select listagg(distinct the_column, ',') within group (order by the_column)
from the_table
18c and earlier:
select listagg(the_column, ',') within group (order by the_column)
from (
select distinct the_column
from t...
Check if table exists and if it doesn't exist, create it in SQL Server 2008
...
Something like this
IF NOT EXISTS (SELECT * FROM sys.objects
WHERE object_id = OBJECT_ID(N'[dbo].[YourTable]') AND type in (N'U'))
BEGIN
CREATE TABLE [dbo].[YourTable](
....
....
....
)
END
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Conveniently Declaring Compile-Time Strings in C++
...y cumbersome, as the string needs to be declared as a variadic sequence of characters, e.g.
15 Answers
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How can I change my default database in SQL Server without using MS SQL Server Management Studio?
...nagement Studio by using the 'options' button in the connection dialog and selecting 'master' as the database to connect to. However, whenever I try to do anything in object explorer, it tries to connect using my default database and fails.
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