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Select last N rows from MySQL
I want to select last 50 rows from MySQL database within column named id which is primary key . Goal is that the rows should be sorted by id in ASC order, that’s why this query isn’t working
...
Transaction isolation levels relation with locks on table
... writes data and commit/rollback (depending on results). B just executes a SELECT statement to read data. C reads and updates data. All these process work on the same table T.
READ UNCOMMITTED - no lock on the table. You can read data in the table while writing on it. This means A writes data (unc...
Rails: Using greater than/less than with a where statement
...s behavior.
User.where(id: 201..Float::INFINITY)
will generate the SQL
SELECT `users`.* FROM `users` WHERE (`users`.`id` >= 201)
The same can be done for less than with -Float::INFINITY.
I just posted a similar question asking about doing this with dates here on SO.
>= vs >
To avo...
Filter by property
...ral models, and this routine should work for all models. And it does:
def selectByProperties(modelType, specify):
clause = "SELECT * from %s" % modelType._meta.db_table
if len(specify) > 0:
clause += " WHERE "
for field, eqvalue in specify.items():
clause += ...
How to delete a workspace in Eclipse?
...Mac OS, once you have deleted the actual workspace directory the option to select and switch to that workspace will still be available unless you delete the entry from Preferences >> General >> Startup and Shutdown >> Workspaces.
...
How to deselect a selected UITableView cell?
I am working on a project on which I have to preselect a particular cell.
24 Answers
2...
How to check date of last change in stored procedure or function in SQL server
...
SELECT name, create_date, modify_date
FROM sys.objects
WHERE type = 'P'
ORDER BY modify_date DESC
The type for a function is FN rather than P for procedure. Or you can filter on the name column.
...
IN clause and placeholders
...mes = { "name1", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host pa...
LINQ with groupby and count
...(var line in data.GroupBy(info => info.metric)
.Select(group => new {
Metric = group.Key,
Count = group.Count()
})
.OrderBy(x => x.Metric))
{
Console.Wri...
How do I prompt for Yes/No/Cancel input in a Linux shell script?
...";;
esac
done
Another method, pointed out by Steven Huwig, is Bash's select command. Here is the same example using select:
echo "Do you wish to install this program?"
select yn in "Yes" "No"; do
case $yn in
Yes ) make install; break;;
No ) exit;;
esac
done
With sele...