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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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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.
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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 to allow only one radio button to be checked?
... set "groups" of radio buttons, only one radio button in each group can be selected at one time and selecting other will clear the previous selection. :)
– Shadow Wizard is Ear For You
Mar 24 '11 at 13:02
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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...
Return number of rows affected by UPDATE statements
...NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @RowCount1 INTEGER
DECLARE @RowCount2 INTEGER
DECLARE @RowCount3 INTEGER
DECLARE @RowCount4 INTEGER
UPDATE Table1 Set Column = 0 WHERE Column IS NULL
SEL...
Set selected option of select box
I want to set a option that was selected previously to be displayed on page load. I tried it with the following code:
16 An...
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 ...
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 ...