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How do I drop a function if it already exists?
...
IF EXISTS (
SELECT * FROM sysobjects WHERE id = object_id(N'function_name')
AND xtype IN (N'FN', N'IF', N'TF')
)
DROP FUNCTION function_name
GO
If you want to avoid the sys* tables, you could instead do (from here in example A...
Java's L number (long) specification
... 3.14159), it is assumed to be a double.
In all other cases (byte, short, char), you need the cast as there is no specific suffix.
The Java spec allows both upper and lower case suffixes, but the upper case version for longs is preferred, as the upper case L is less easy to confuse with a numeral ...
In SQL, what's the difference between count(column) and count(*)?
...a values(null,1)
insert #bla values(1,null)
insert #bla values(null,null)
select count(*),count(id),count(id2)
from #bla
results
7 3 2
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What's the difference between MyISAM and InnoDB? [duplicate]
... on the table, and while that lock is held, no other session can perform a SELECT or a DML operation on the table.
Those two specific engines you asked about (InnoDB and MyISAM) have different design goals. MySQL also has other storage engines, with their own design goals.
So, in choosing between In...
Querying data by joining two tables in two database on different servers
...just prefixing the database name with the other server. I.E:
-- FROM DB1
SELECT *
FROM [MyDatabaseOnDB1].[dbo].[MyTable] tab1
INNER JOIN [DB2].[MyDatabaseOnDB2].[dbo].[MyOtherTable] tab2
ON tab1.ID = tab2.ID
Once the link is established, you can also use OPENQUERY to execute a SQL st...
What is SQL injection? [duplicate]
...ue for any language), which might be used to handle a user login.
$sql = "SELECT FROM users WHERE username='".$_GET['username']."' AND password='".$_GET['password']."'";
The harm is done when the user enters something like
administrator'; --
... for the username. Without proper encoding the...
How do I use Java to read from a file that is actively being written to?
...{
if( reader.available() > 0 ) {
System.out.print( (char)reader.read() );
}
else {
try {
sleep( 500 );
}
catch( InterruptedException ex ) {
running = false;
}
}
}
}
Of...
Branch descriptions in Git
... with commits 6f9a332, 739453a3, b7200e8:
struct branch_desc_cb {
const char *config_name;
const char *value;
};
--edit-description::
Open an editor and edit the text to explain what the branch is for, to be used by various other commands (e.g. request-pull).
Note that it won't work for...
How to check which locks are held on a table
...pful to you.
You can check which statements are blocked by running this:
select cmd,* from sys.sysprocesses
where blocked > 0
It will also tell you what each block is waiting on. So you can trace that all the way up to see which statement caused the first block that caused the other blocks.
...
How to parse freeform street/postal address out of text, and into components
...ybe you have a good way to deal with single-field US addresses, so if they select United States, you can reduce your form to a single field, otherwise show the component fields. Just things to think about!
Now we know why it's hard; what can you do about it?
The USPS licenses vendors through a proce...