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Naming convention for unique constraint
...imary key doesn't get a sequence number since there can be only one. The 2-char alpha suffix meanings are:
PK: Primary Key
AK: Alternate Key
FK: Foreign Key
IX: IndeX
CK: ChecK
DF: DeFault
I generally want to group metadata/system catalog data by the controlling object rather than by object type...
How do I convert an interval into a number of hours with postgres?
...
Probably the easiest way is:
SELECT EXTRACT(epoch FROM my_interval)/3600
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SQL error “ORA-01722: invalid number”
...
Well it also can be :
SELECT t.col1, t.col2, ('test' + t.col3) as test_col3
FROM table t;
where for concatenation in oracle is used the operator || not +.
In this case you get : ORA-01722: invalid number ...
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Remove Identity from a column in a table
...USTERED INDEX IX_Original_Value ON Original (Value);
INSERT INTO Original
SELECT 'abcd'
UNION ALL
SELECT 'defg';
You can do the following:
--create new table with no IDENTITY
CREATE TABLE Original2
(
Id INT PRIMARY KEY
, Value NVARCHAR(300)
);
CREATE NONCLUSTERED INDEX IX_Original_Value2 ON O...
Code Wrap IntelliJ?
...o right click the gutter (the vertical bar where line number is shown) and select "Use Soft wraps" - thanks to Bajal for comment.
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Is it possible to select the last n items with nth-child?
Using a standard list, I'm trying to select the last 2 list items. I've various permutations of An+B but nothing seems to select the last 2:
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Mac SQLite editor [closed]
... info.plist and setting it to YES
Running the app on a device
Open iTunes
Select the device
Select the "Apps" tab
Scroll down to the "File Sharing" section and select the app
The .sqlite file should appear in the right hand pane - select it and "Save to..."
Once it's saved open it up in your favour...
LINQ query on a DataTable
...w in myDataTable.AsEnumerable()
where myRow.Field<int>("RowNo") == 1
select myRow;
And as @Keith says, you'll need to add a reference to System.Data.DataSetExtensions
AsEnumerable() returns IEnumerable<DataRow>. If you need to convert IEnumerable<DataRow> to a DataTable, use the...
SQL “between” not inclusive
... is interpreted as midnight when the day starts.
One way to fix this is:
SELECT *
FROM Cases
WHERE cast(created_at as date) BETWEEN '2013-05-01' AND '2013-05-01'
Another way to fix it is with explicit binary comparisons
SELECT *
FROM Cases
WHERE created_at >= '2013-05-01' AND created_at <...
ASP.NET MVC Html.DropDownList SelectedValue
...m:
I had the following:
Controller:
ViewData["DealerTypes"] = Helper.SetSelectedValue(listOfValues, selectedValue) ;
View
<%=Html.DropDownList("DealerTypes", ViewData["DealerTypes"] as SelectList)%>
Changed by the following:
View
<%=Html.DropDownList("DealerTypesDD", ViewData["De...