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What is the difference between HAVING and WHERE in SQL?
What is the difference between HAVING and WHERE in an SQL SELECT statement?
20 Answers
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Android requires compiler compliance level 5.0 or 6.0. Found '1.7' instead. Please use Android Tools
....0 or Java 6.0.
To do that, 2 options:
Right-click on your project and select "Android Tools -> Fix
Project Properties" (if this din't work, try second option)
Right-click on your project and select "Properties -> Java
Compiler", check "Enable project specific settings" and select
1.5 ...
How do I get the size of a java.sql.ResultSet?
...
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...
How to copy a row and insert in same table with a autoincrement field in MySQL?
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Use INSERT ... SELECT:
insert into your_table (c1, c2, ...)
select c1, c2, ...
from your_table
where id = 1
where c1, c2, ... are all the columns except id. If you want to explicitly insert with an id of 2 then include that in your INSER...
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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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...
Selecting only first-level elements in jquery
How can I select the link elements of only the parent <ul> from a list like this?
10 Answers
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MySQL “Group By” and “Order By”
I want to be able to select a bunch of rows from a table of e-mails and group them by the from sender. My query looks like this:
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How to find all duplicate from a List? [duplicate]
...d then filter out any of the enumerables that have a Count of <=1, then select their keys to get back down to a single enumerable:
var duplicateKeys = list.GroupBy(x => x)
.Where(group => group.Count() > 1)
.Select(group => group.Key);
...
How do you determine what SQL Tables have an identity column programmatically
...ct to change, version to version) is to use the
INFORMATION_SCHEMA views:
select COLUMN_NAME, TABLE_NAME
from INFORMATION_SCHEMA.COLUMNS
where COLUMNPROPERTY(object_id(TABLE_SCHEMA+'.'+TABLE_NAME), COLUMN_NAME, 'IsIdentity') = 1
order by TABLE_NAME
...