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Rails new vs create
...fferently.
An HTTP GET to /resources/new is intended to render a form suitable for creating a new resource, which it does by calling the new action within the controller, which creates a new unsaved record and renders the form.
An HTTP POST to /resources takes the record created as part of the ne...
Is there any difference between GROUP BY and DISTINCT
...river :: GroupBy : Distinct and screw => get list of unique values in a table column)
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How to use phpexcel to read data and insert into database?
...';
echo ' and ' . $highestRow . ' row.';
echo '<br>Data: <table border="1"><tr>';
//----- loop from all rows -----
for ($row = 1; $row <= $highestRow; ++ $row)
{
echo '<tr>';
echo "<td>".$row."</td>";
//--- read each...
Why can't I use switch statement on a String?
...nse, they are used as an index (after subtracting the lowest value) into a table of instruction pointers—the tableswitch instruction.
If the constants are sparse, a binary search for the correct case is performed—the lookupswitch instruction.
In de-sugaring a switch on String objects, both i...
Select something that has more/less than x character
...L Server, Use the LEN (Length) function:
SELECT EmployeeName FROM EmployeeTable WHERE LEN(EmployeeName) > 4
MSDN for it states:
Returns the number of characters of the specified string expression,
excluding trailing blanks.
Here's the link to the MSDN
For oracle/plsql you can use Leng...
Is it a good idea to index datetime field in mysql?
.... In my application I will have many rows for example I currently have one table with 4 million records. Most of my queries use datetime clause to select data. Is it a good idea to index datetime fields in mysql database?
...
ERROR: permission denied for sequence cities_id_seq using Postgres
...
Interesting. I did a GRANT all on the table that my sequence is in, but this doesn't seem to cover the sequence. This also seems to very by OS.
– Kinnard Hockenhull
Jun 7 '14 at 15:48
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Should try…catch go inside or outside a loop?
...ch structures are placed. Internally, they are implemented as a code-range table in a structure that is created when the method is called. While the method is executing, the try/catch structures are completely out of the picture unless a throw occurs, then the location of the error is compared again...
How to use Oracle ORDER BY and ROWNUM correctly?
...ory, in Oracle, you need to limit the results manually when you have large tables and/or tables with same column names (and you don't want to explicit type them all out and rename them all). Easy solution is to figure out your breakpoint and limit that in your query. Or you could also do this in the...
SQL Server Profiler - How to filter trace to only display events from one database?
...lumn and find out the correct values to enter by querying the sysdatabases table in the master database
– Jim Birchall
Nov 10 '08 at 8:39
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