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How to copy a row and insert in same table with a autoincrement field in MySQL?
... id=NULL may cause an error Column 'id' cannot be null. Should be replaced by UPDATE temp_table SET id = (SELECT MAX(id) + 1 as id FROM your_table);
– Modder
May 31 '17 at 15:41
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How do I stop Entity Framework from trying to save/insert child objects?
...t with database object? Why should we need to take care of the association by ourselves? Taking care of the navigation property during adding new object is something like moving the database operations from SQL to C#, cumbersome to the developers.
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Hibernate Criteria returns children multiple times with FetchType.EAGER
...n
So actually it should apear multiple times. this is explained very well by the author (Gavin King) himself here:
It both explains why, and how to still get distinct results
Also mentioned in the Hibernate FAQ :
Hibernate does not return distinct results for a query with outer join fetching...
How to force use of overflow menu on devices with menu button
...wer for the situation of physical menu button.
This is actually prevented by design. According to the Compatibility Section of the Android Design Guide,
"...the action overflow is available from the menu hardware key. The resulting actions popup... is displayed at the bottom of the screen."
You...
Add a column to existing table and uniquely number them on MS SQL Server
...to add a column to an existing legacy database and write a procedure by which I can assign each record a different value. Something like adding a column and autogenerate the data for it.
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How to select/get drop down option in Selenium 2
... option based on the label:
Select select = new Select(driver.findElement(By.xpath("//path_to_drop_down")));
select.deselectAll();
select.selectByVisibleText("Value1");
To get the first selected value:
WebElement option = select.getFirstSelectedOption()
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Eager load polymorphic
... Review and Shop since it allows you to eager load in addition to querying by related fields.
The reason that this is necessary is that ActiveRecord cannot build a join based on reviewable alone, since multiple tables represent the other end of the join, and SQL, as far as I know, does not allow yo...
Copying files from Docker container to host
...rent running user. That is, the files in /artifacts will be shown as owned by the user with the UID of the user used inside the docker container. A way around this may be to use the calling user's UID:
docker run -i -v ${PWD}:/working_dir -w /working_dir -u $(id -u) \
ubuntu:14.04 sh << C...
How to properly create composite primary keys - MYSQL
...xing purposes then correct? As in I wouldn't be able to reference a record by using this composite, I would still have to so do an UPDATE info ... WHERE t1ID=11209 AND t2ID=437 ?
– filip
Apr 29 '11 at 20:28
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In SQL, what's the difference between count(column) and count(*)?
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@tsilb: The answer posted by @Alan states "count(*) is computed by looking at the indexes on the table in question rather than the actual data rows" which, if true, invalidates your comment. I appreciate that @Alan may be wrong but I'm interested in t...