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MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...
When should I use nil and NULL in Objective-C?
...ke a C pointer) in Objective-C. Like nil , NULL got no value nor address.
char *myChar = NULL;
struct MyStruct *dStruct = NULL;
So if there is a situation, when I need to check my struct (structure type variable) is empty or not then, I will use:
if (dStruct == NULL)
NSLog("The struct is emp...
How to convert SecureString to System.String?
...e(value);
for (int i=0; i < value.Length; i++) {
short unicodeChar = Marshal.ReadInt16(valuePtr, i*2);
// handle unicodeChar
}
} finally {
Marshal.ZeroFreeGlobalAllocUnicode(valuePtr);
}
}
sha...
cpuid汇编指令 - C/C++ - 清泛网 - 专注C/C++及内核技术
... spaces
cmp al, 0
jz done
disp_char:
mov dl, al
mov ah, 2
int 21h
lodsb
cmp al, 0
jnz disp_char
done:
mov ax, 4c...
How do you copy a record in a SQL table but swap out the unique id of the new row?
...
Try this:
insert into MyTable(field1, field2, id_backup)
select field1, field2, uniqueId from MyTable where uniqueId = @Id;
Any fields not specified should receive their default value (which is usually NULL when not defined).
...
How to copy a row and insert in same table with a autoincrement field in MySQL?
...
Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSER...
Rails 3: Get Random Record
...You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where id >= trunc(
random() * (select max(id) from my_table) + 1
)
order by id
limit 1;
share
|
...
List of Timezone ID's for use with FindTimeZoneById() in C#?
...
And if you'd like a HTML select with the Windows time zones in:
<select>
<option value="Morocco Standard Time">(GMT) Casablanca</option>
<option value="GMT Standard Time">(GMT) Greenwich Mean Time : Dublin, Edinburgh, Lisbon,...
how to exclude null values in array_agg like in string_agg using postgres?
...
SQL Fiddle
select
id,
(select array_agg(a) from unnest(canonical_users) a where a is not null) canonical_users,
(select array_agg(a) from unnest(non_canonical_users) a where a is not null) non_canonical_users
from (
SELE...
What is the error “Every derived table must have its own alias” in MySQL?
...er), which can the be used to refer to it in the rest of the outer query.
SELECT ID FROM (
SELECT ID, msisdn FROM (
SELECT * FROM TT2
) AS T
) AS T
In your case, of course, the entire query could be replaced with:
SELECT ID FROM TT2
...