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What must I know to use GNU Screen properly? [closed]
... target window. Warning: it will let you know if anything changes.
Want to select window 15 directly? Try these in your .screenrc file:
bind ! select 11
bind @ select 12
bind \# select 13
bind $ select 14
bind % select 15
bind \^ select 16
bind & select 17
bind * select 18
bind ( selec...
How do I get the size of a java.sql.ResultSet?
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Do a SELECT COUNT(*) FROM ... query instead.
OR
int size =0;
if (rs != null)
{
rs.last(); // moves cursor to the last row
size = rs.getRow(); // get row id
}
In either of the case, you won't have to loop over the enti...
SQL NVARCHAR and VARCHAR Limits
... large (unavoidable) dynamic SQL query. Due to the number of fields in the selection criteria the string containing the dynamic SQL is growing over 4000 chars. Now, I understand that there is a 4000 max set for NVARCHAR(MAX) , but looking at the executed SQL in Server Profiler for the statement
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View's SELECT contains a subquery in the FROM clause
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As per documentation:
MySQL Docs
The SELECT statement cannot contain a subquery in the FROM clause.
Your workaround would be to create a view for each of your subqueries.
Then access those views from within your view view_credit_status
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Counting DISTINCT over multiple columns
... function turns the ints into varchars to make the distinct more reliable
SELECT COUNT(DISTINCT (CHECKSUM(DocumentId,DocumentSessionId)) + CHECKSUM(REVERSE(DocumentId),REVERSE(DocumentSessionId)) )
FROM DocumentOutPutItems
...
LEFT OUTER JOIN in LINQ
...c.Category equals p.Category into ps
from p in ps.DefaultIfEmpty()
select new { Category = c, ProductName = p == null ? "(No products)" : p.ProductName };
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How to check if field is null or empty in MySQL?
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Either use
SELECT IF(field1 IS NULL or field1 = '', 'empty', field1) as field1
from tablename
or
SELECT case when field1 IS NULL or field1 = ''
then 'empty'
else field1
end as field1
from tablename
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MySQL IF NOT NULL, then display 1, else display 0
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SELECT c.name, IF(a.addressid IS NULL,0,1) AS addressexists
FROM customers c
LEFT JOIN addresses a ON c.customerid = a.customerid
WHERE customerid = 123
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Replacement for “rename” in dplyr
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The next version of dplyr will support an improved version of select that also incorporates renaming:
> mtcars2 <- select( mtcars, disp2 = disp )
> head( mtcars2 )
disp2
Mazda RX4 160
Mazda RX4 Wag 160
Datsun 710 108
Hornet 4 Drive 258
H...
Search text in fields in every table of a MySQL database
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If you have phpMyAdmin installed use its 'Search' feature.
Select your DB
Be sure you do have a DB selected (i.e. not a table, otherwise you'll get a completely different search dialog)
Click 'Search' tab
Choose the search term you want
Choose the tables to search
I have used this ...