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Find the number of columns in a table
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SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_catalog = 'database_name' -- the database
AND table_name = 'table_name'
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What makes a SQL statement sargable?
...non-sargable is to include a field inside a function in the where clause:
SELECT ... FROM ...
WHERE Year(myDate) = 2008
The SQL optimizer can't use an index on myDate, even if one exists. It will literally have to evaluate this function for every row of the table. Much better to use:
WHERE myDat...
How to print SQL statement in codeigniter model
...veRecord generated SQL:
Before the query runs:
$this->db->_compile_select();
And after it has run:
$this->db->last_query();
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Are PDO prepared statements sufficient to prevent SQL injection?
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$pdo->query('SET NAMES gbk');
$var = "\xbf\x27 OR 1=1 /*";
$query = 'SELECT * FROM test WHERE name = ? LIMIT 1';
$stmt = $pdo->prepare($query);
$stmt->execute(array($var));
In certain circumstances, that will return more than 1 row. Let's dissect what's going on here:
Selecting a Cha...
How do I run Visual Studio as an administrator by default?
...indows 8, 8.1 and 10
In Windows 8, you have to right-click devenv.exe and select "Troubleshoot compatibility".
Select "Troubleshoot program"
Check "The program requires additional permissions"
click "Next", click "Test the program..."
Wait for the program to launch
Click "Next"
Select "Yes, save ...
How to set selected item of Spinner by value, not by position?
I have a update view, where I need to preselect the value stored in database for a Spinner.
25 Answers
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How to increase storage for Android Emulator? (INSTALL_FAILED_INSUFFICIENT_STORAGE)
...onfigurations". You can find that in the drop-down under the "debug" icon. Select "target", and select a preferred emulator target to launch. Then under "additional emulator command line options," add this:
-partition-size 1024
Then CLOSE the emulator (and remove any devices), and click the debug ...
List of tables, db schema, dump etc using the Python sqlite3 API
....tab
job snmptarget t1 t2 t3
sqlite> select name from sqlite_master where type = 'table';
job
t1
t2
snmptarget
t3
sqlite> .schema job
CREATE TABLE job (
id INTEGER PRIMARY KEY,
data VARCHAR
);
sqlite> select sql from sqlite_master where type = 'ta...
Get current AUTO_INCREMENT value for any table
...'TableName' ;
You can get exactly this information by using this query:
SELECT `AUTO_INCREMENT`
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'DatabaseName'
AND TABLE_NAME = 'TableName';
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How to get all Errors from ASP.Net MVC modelState?
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Using LINQ:
IEnumerable<ModelError> allErrors = ModelState.Values.SelectMany(v => v.Errors);
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