大约有 43,000 项符合查询结果(耗时:0.0505秒) [XML]
Get the last inserted row ID (with SQL statement) [duplicate]
...alue using:
INSERT INTO dbo.YourTable(columns....)
VALUES(..........)
SELECT SCOPE_IDENTITY()
This works as long as you haven't inserted another row - it just returns the last IDENTITY value handed out in this scope here.
There are at least two more options - @@IDENTITY and IDENT_CURRENT - r...
Why do we always prefer using parameters in SQL statements?
I am very new to working with databases. Now I can write SELECT , UPDATE , DELETE , and INSERT commands. But I have seen many forums where we prefer to write:
...
jQuery $(“#radioButton”).change(…) not firing during de-selection
...Andomar's solution worked but this makes more sense to me. Using the class selector prevents having to change the function if the form changes or has a dynamic number of fields. Yay for necro votes! (though now 2 years later jQuery recommends using prop() instead of attr(). api.jquery.com/prop)
...
Regex (grep) for multi-line search needed [duplicate]
I'm running a grep to find any *.sql file that has the word select followed by the word customerName followed by the word from . This select statement can span many lines and can contain tabs and newlines.
...
String is immutable. What exactly is the meaning? [duplicate]
...
A string is a char[] containing a series of UTF-16 code units, an int offset into that array, and an int length.
For example.
String s
It creates space for a string reference. Assigning copies references around but does not modify the...
How to check for Is not Null And Is not Empty string in SQL server?
... ('A'),
(''),
(' '),
(NULL);
SELECT *
FROM T
WHERE C <> ''
Returns just the single row A. I.e. The rows with NULL or an empty string or a string consisting entirely of spaces are all excluded by this query.
SQL Fiddle
...
Swapping column values in MySQL
...rows affected (0.08 sec)
Records: 4 Duplicates: 0 Warnings: 0
mysql> SELECT * FROM swaptest;
+------+------+
| X | Y |
+------+------+
| 1 | 2 |
| 3 | 4 |
| -5 | -8 |
| -13 | 27 |
+------+------+
4 rows in set (0.00 sec)
mysql>
Here is the swap being performed
m...
SQL JOIN vs IN performance?
...king, IN and JOIN are different queries that can yield different results.
SELECT a.*
FROM a
JOIN b
ON a.col = b.col
is not the same as
SELECT a.*
FROM a
WHERE col IN
(
SELECT col
FROM b
)
, unless b.col is unique.
However, this is the syno...
LINQ query on a DataTable
...w in myDataTable.AsEnumerable()
where myRow.Field<int>("RowNo") == 1
select myRow;
And as @Keith says, you'll need to add a reference to System.Data.DataSetExtensions
AsEnumerable() returns IEnumerable<DataRow>. If you need to convert IEnumerable<DataRow> to a DataTable, use the...
Convert NSData to String?
...lowing code works for me where pkey is a pointer to an EVP_PKEY:
unsigned char *buf, *pp;
int len = i2d_PrivateKey(pkey, NULL);
buf = OPENSSL_malloc(len);
pp = buf;
i2d_PrivateKey(pkey, &pp);
NSData* pkeyData = [NSData dataWithBytes:(const void *)buf length:len];
DLog(@"Private key in hex (%d...