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Eclipse doesn't highlight references anymore
... If none of comments above worked, uncheck "Mark occurrences of the selected element in the current file" > Apply > OK. Go back to preferences, check "Mark occurrences of the selected element in the current file" > Apply > OK.
– realPK
Feb 4 ...
Dynamically select data frame columns using $ and a character value
...and some variable names stored in a character vector cols . When I try to select a variable from mtcars using a dynamic subset of cols , nether of these work
...
Django select only rows with duplicate field values
...ithout this, the subquery fails. The extra values tricks the ORM into only selecting the name column for the subquery.
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How do I create a SQL table under a different schema?
...er 2008
1. Navigate to Security > Schemas
2. Right click on Schemas and select New Schema
3. Complete the details in the General tab for the new schema. Like, the schema name is "MySchema" and the schema owner is "Admin".
4. Add users to the schema as required and set their permissions:
5. Add an...
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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How to check all checkboxes using jQuery?
...});
Html should be :
Single check box on checked three checkbox will be select and deselect.
<input type="checkbox" name="checkedAll" id="checkedAll" />
<input type="checkbox" name="checkAll" class="checkSingle" />
<input type="checkbox" name="checkAll" class="checkSingle" />
...
SQLite UPSERT / UPDATE OR INSERT
... at this code:
INSERT INTO players (id, name, age)
VALUES (
coalesce((select id from players where user_name='steven'),
(select max(id) from drawings) + 1),
32)
The trick is in coalesce. It returns the id of the user 'steven' if any, and otherwise, it returns a new fresh id.
...
How to get ERD diagram for an existing database?
...t that up in Manage, in which case all your databases will be available to select in step 3)
Import all objects (it will warn that you are importing to the current model, which is fine since it is empty).
Now switch back to the Design tab to see your ERD.
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How can i query for null values in entity framework?
...try in table
where entry.something.Equals(value)
select entry;
Workaround for Linq-to-Entities (ouch!):
var result = from entry in table
where (value == null ? entry.something == null : entry.something == value)
select entry;
This is a nasty b...
Concatenate multiple result rows of one column into one, group by another column [duplicate]
...Simpler with the aggregate function string_agg() (Postgres 9.0 or later):
SELECT movie, string_agg(actor, ', ') AS actor_list
FROM tbl
GROUP BY 1;
The 1 in GROUP BY 1 is a positional reference and a shortcut for GROUP BY movie in this case.
string_agg() expects data type text as input. Other ...