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How to Select Every Row Where Column Value is NOT Distinct
I need to run a select statement that returns all rows where the value of a column is not distinct (e.g. EmailAddress).
7 A...
Modifying a subset of rows in a pandas dataframe
...The df.A==0 expression creates a boolean series that indexes the rows, 'B' selects the column. You can also use this to transform a subset of a column, e.g.:
df.loc[df.A==0, 'B'] = df.loc[df.A==0, 'B'] / 2
I don't know enough about pandas internals to know exactly why that works, but the basic is...
String.Join method that ignores empty strings?
... simpler, since you can do it in SQL directly:
PostgreSQL & MySQL:
SELECT
concat_ws(' / '
, NULLIF(searchTerm1, '')
, NULLIF(searchTerm2, '')
, NULLIF(searchTerm3, '')
, NULLIF(searchTerm4, '')
) AS RPT_SearchTerms;
And even with the glorious MS-SQ...
Linq to Sql: Multiple left outer joins
... .Where(s => s.Id == order.StatusId)
.DefaultIfEmpty()
select new { Order = order, Vendor = vendor, Status = status }
//Vendor and Status properties will be null if the left join is null
Here is another left join example
var results =
from expense in expenseDataConte...
SQL Server principal “dbo” does not exist,
...
Do Graphically.
Database right click-->properties-->files-->select database owner-->select [sa]-- ok
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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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Obtain form input fields using jQuery?
...s[field.name] = field.value;
});
Note that this snippet will fail on <select multiple> elements.
It appears that the new HTML 5 form inputs don't work with serializeArray in jQuery version 1.3. This works in version 1.4+
...
How to select following sibling/xml tag using xpath
... we are interested in. In this case you can omit ./ . Also, if you want to select the immediate following sibling, use: following-sibling::td[1], otherwise, if there are more than one following siblings, all will be selected.
– Dimitre Novatchev
Jan 23 '16 at 2...
Replacing NULL with 0 in a SQL server query
...u want to replace a possibly null column with something else, use IsNull.
SELECT ISNULL(myColumn, 0 ) FROM myTable
This will put a 0 in myColumn if it is null in the first place.
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Equivalent of LIMIT and OFFSET for SQL Server?
...nation it's better to write a query like this:
;WITH Results_CTE AS
(
SELECT
Col1, Col2, ...,
ROW_NUMBER() OVER (ORDER BY SortCol1, SortCol2, ...) AS RowNum
FROM Table
WHERE <whatever>
)
SELECT *
FROM Results_CTE
WHERE RowNum >= @Offset
AND RowNum < @Offset +...
