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INSERT IF NOT EXISTS ELSE UPDATE?
...ot in the insert list will be set to NULL if the row already exists in the table. This is why there's a subselect for the ID column: In the replacement case the statement would set it to NULL and then a fresh ID would be allocated.
This approach can also be used if you want to leave particular fiel...
UITableView Cell selected Color?
I have created a custom UITableViewCell . The table view is showing data fine. What I am stuck in is when user touches cell of tableview, then I want to show the background color of the cell other than the default [blue color] values for highlighting the selection of cell.
I use this code but nothi...
Add default value of datetime field in SQL Server to a timestamp
I've got a table that collects forms submitted from our website, but for some reason, when they created the table, they didn't put a timestamp in the table. I want it to enter the exact date and time that the record was entered.
...
Efficient Algorithm for Bit Reversal (from MSB->LSB to LSB->MSB) in C
...
NOTE: All algorithms below are in C, but should be portable to your language of choice (just don't look at me when they're not as fast :)
Options
Low Memory (32-bit int, 32-bit machine)(from here):
unsigned int
reverse(register unsigned int x)
{
x = (((x & 0xaaaaaaaa)...
WHERE vs HAVING
... answers on this question didn't hit upon the key point.
Assume we have a table:
CREATE TABLE `table` (
`id` int(10) unsigned NOT NULL AUTO_INCREMENT,
`value` int(10) unsigned NOT NULL,
PRIMARY KEY (`id`),
KEY `value` (`value`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8
And have 10 rows with both ...
Storing images in SQL Server?
...pending on your use
If you decide to put your pictures into a SQL Server table, I would strongly recommend using a separate table for storing those pictures - do not store the employee photo in the employee table - keep them in a separate table. That way, the Employee table can stay lean and mean ...
SQL Server indexes - ascending or descending, what difference does it make?
...rily matters when used with composite indexes:
CREATE INDEX ix_index ON mytable (col1, col2 DESC);
can be used for either:
SELECT *
FROM mytable
ORDER BY
col1, col2 DESC
or:
SELECT *
FROM mytable
ORDER BY
col1 DESC, col2
, but not for:
SELECT *
FROM mytable
ORDE...
How to generate an entity-relationship (ER) diagram using Oracle SQL Developer
I want to use Oracle SQL Developer to generate an ER diagram for my DB tables but I am new to Oracle and this tool.
8 Answe...
Set default value of an integer column SQLite
...
Use the SQLite keyword default
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " ("
+ KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_NAME + " TEXT NOT NULL, "
+ KEY_WORKED + " INTEGER, "
+ KEY_NOTE + " INTEGER DEFAULT 0);");
This link is useful: ht...
What is the difference between HAVING and WHERE in SQL?
..., CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Gives you a table of all cities in MA and the number of addresses in each city.
This code:
select City, CNT=Count(1)
From Address
Where State = 'MA'
Group By City
Having Count(1)>5
Gives you a table of cities in MA with more than ...