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Importance of varchar length in MySQL table
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Anytime your select query uses a temporary table (group and order by operations, among other things) it will convert varchar(200) to a char(200) and performance will suffer.
– Jamie
Feb 7 '13 at 20:1...
Store boolean value in SQLite
...TO foo VALUES("0.0");
sqlite> INSERT INTO foo VALUES("1.0");
sqlite> select mycolumn, typeof(mycolumn) from foo;
0|integer
1|integer
0|integer
1|integer
0|integer
1|integer
and some that will fail:
sqlite> INSERT INTO foo VALUES("-1");
Error: constraint failed
sqlite> INSERT INTO foo ...
How To Test if Type is Primitive
...
where t.IsValueType
select typeof (Nullable<>).MakeGenericType(t);
List = types.Concat(nullTypes).ToArray();
}
public static bool Test(Type type)
{
if (List.Any(x => x.IsAssignableFrom(type))...
Int to Char in C#
What is the best way to convert an Int value to the corresponding Char in Utf16, given that the Int is in the range of valid values?
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What is the size of column of int(11) in mysql in bytes?
...ytes (64 bit).
The length just specifies how many characters to pad when selecting data with the mysql command line client. 12345 stored as int(3) will still show as 12345, but if it was stored as int(10) it would still display as 12345, but you would have the option to pad the first five digits. ...
How to display a dynamically allocated array in the Visual Studio debugger?
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For beginners: If you select "a" variable, right click and add to watch list (inspect), if you open de debugger view in the list of watched values (I can't find the name of the window right now), you can double click "a" and rename it "a,X" where ...
How to assign an exec result to a sql variable?
...esultForPos INT
EXEC @ResultForPos = storedprocedureName 'InputParameter'
SELECT @ResultForPos
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What is the meaning of the prefix N in T-SQL statements and when should I use it?
...1. It is an Nvarchar
This query fails to match Exact Value That Exists.
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = 'ESKİ'
// 0 result
using prefix N'' fixes it
SELECT TOP 1 * FROM myTable1 WHERE MyCol1 = N'ESKİ'
// 1 result - found!!!!
Why? Because latin1_general doesn't have big...
How can you make a custom keyboard in Android?
...) {
case Keyboard.KEYCODE_DELETE:
CharSequence selectedText = ic.getSelectedText(0);
if (TextUtils.isEmpty(selectedText)) {
// no selection, so delete previous character
ic.deleteSurroundingText(1, 0);
...
How do I print the full value of a long string in gdb?
...rinting a SQL query results in:
(gdb) x/300sb stmt.c_str()
0x9cd948: "SELECT article.r"...
0x9cd958: "owid FROM articl"...
..
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