大约有 41,000 项符合查询结果（耗时：0.0420秒） [XML]
How to initialize a struct in accordance with C programming language standards
...lize a struct this way:
typedef struct Item {
int a;
float b;
char* name;
} Item;
int main(void) {
Item item = { 5, 2.2, "George" };
return 0;
}
An important thing to remember, at the moment you initialize even one object/ variable in the struct, all of its other variables wi...
How does the Comma Operator work
...’t work since then the compiler just sees the comma operator between two char[], which cannot be overloaded. The code intentionally first calls the operator= and then subsequently operator, for each remaining element.
– Konrad Rudolph
Oct 9 '11 at 11:04
...
Generate random int value from 3 to 6
...
This generates a random number between 0-9
SELECT ABS(CHECKSUM(NEWID()) % 10)
1 through 6
SELECT ABS(CHECKSUM(NEWID()) % 6) + 1
3 through 6
SELECT ABS(CHECKSUM(NEWID()) % 4) + 3
Dynamic (Based on Eilert Hjelmeseths Comment)
SELECT ABS(CHECKSUM(NEWID()) % (@ma...
How do I capitalize first letter of first name and last name in C#?
...
TextInfo.ToTitleCase() capitalizes the first character in each token of a string.
If there is no need to maintain Acronym Uppercasing, then you should include ToLower().
string s = "JOHN DOE";
s = CultureInfo.CurrentCulture.TextInfo.ToTitleCase(s.ToLower());
// Produce...
typecast string to integer - Postgres
...ur value is an empty string, you can use NULLIF to replace it for a NULL:
SELECT
NULLIF(your_value, '')::int
share
|
improve this answer
|
follow
|
...
How to delete duplicate rows in SQL Server?
... are deleted (or updated), therefore just change the DELETE FROM CTE... to SELECT * FROM CTE:
WITH CTE AS(
SELECT [col1], [col2], [col3], [col4], [col5], [col6], [col7],
RN = ROW_NUMBER()OVER(PARTITION BY col1 ORDER BY col1)
FROM dbo.Table1
)
DELETE FROM CTE WHERE RN > 1
DEMO (re...
Difference between “read commited” and “repeatable read”
...nd consider you have a simple task like the following:
BEGIN TRANSACTION;
SELECT * FROM T;
WAITFOR DELAY '00:01:00'
SELECT * FROM T;
COMMIT;
That is a simple task that issue two reads from table T, with a delay of 1 minute between them.
under READ COMMITTED, the second SELECT may return any da...
Removing duplicate rows from table in Oracle
...
Use the rowid pseudocolumn.
DELETE FROM your_table
WHERE rowid not in
(SELECT MIN(rowid)
FROM your_table
GROUP BY column1, column2, column3);
Where column1, column2, and column3 make up the identifying key for each record. You might list all your columns.
...
MySQL “NOT IN” query
...
To use IN, you must have a set, use this syntax instead:
SELECT * FROM Table1 WHERE Table1.principal NOT IN (SELECT principal FROM table2)
share
|
improve this answer
|
...
MySQL Select all columns from one table and some from another table
How do you select all the columns from one table and just some columns from another table using JOIN? In MySQL.
4 Answers
...