大约有 43,000 项符合查询结果（耗时：0.0454秒） [XML]
MySQL: selecting rows where a column is null
I'm having a problem where when I try to select the rows that have a NULL for a certain column, it returns an empty set. However, when I look at the table in phpMyAdmin, it says null for most of the rows.
...
How do I use ROW_NUMBER()?
...
For the first question, why not just use?
SELECT COUNT(*) FROM myTable
to get the count.
And for the second question, the primary key of the row is what should be used to identify a particular row. Don't try and use the row number for that.
If you returned Ro...
Return Boolean Value on SQL Select Statement
How to return a boolean value on SQL Select Statement?
9 Answers
9
...
Html.DropdownListFor selected value not being set
How can I set the selected value of a Html.DropDownListFor? I've been having a look online and have seen that it can be achieved by using the fourth parameter so like the below:
...
Select arrow style change
I'm trying to replace the arrow of a select with a picture of my own. I'm including the select in a div with the same size, I set the background of the select as transparent and I'm including a picture(with the same size as the arrow) in the right top corner of the div as background.
...
How can I list ALL grants a user received?
...ust direct table grants (e.g., grants via roles, system privileges such as select any table, etc.), here are some additional queries:
System privileges for a user:
SELECT PRIVILEGE
FROM sys.dba_sys_privs
WHERE grantee = <theUser>
UNION
SELECT PRIVILEGE
FROM dba_role_privs rp JOIN role_...
What are the differences between poll and select?
I am referring to the POSIX standard select and poll system C API calls.
3 Answers
...
@synthesize vs @dynamic, what are the differences?
... [invocation setReturnValue:&obj];
}
}
@end
int main(int argc, char **argv)
{
NSAutoreleasePool *pool = [[NSAutoreleasePool alloc] init];
Book *book = [[Book alloc] init];
printf("%s is written by %s\n", [book.title UTF8String], [book.author UTF8String]);
book.title = @"...
Using LINQ to remove elements from a List
... {
StringBuilder builder = new StringBuilder();
char ch;
for( int i = 0; i < size; i++ )
{
ch = Convert.ToChar( Convert.ToInt32( Math.Floor( 26 * random.NextDouble() + 65 ) ) );
builder.Append( ch );
}
...
What is the difference between the states selected, checked and activated in Android?
...below added):
... For example, in a list view with single or multiple selection
enabled, the views in the current selection set are activated. (Um,
yeah, we are deeply sorry about the terminology here.) The activated
state is propagated down to children of the view it is set on.
So here...