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SQL - find records from one table which don't exist in another
I've got the following two SQL tables (in MySQL):
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Can someone explain mappedBy in JPA and Hibernate?
...irline that it is responsible for maintaining the values over in the other table. It is possible to tell an Entity it "owns" a column in a different table and is responsible for updating it. It's not something you usually want to do and can cause problems with the order SQL statements are executed...
How to wrap text in LaTeX tables?
I am creating a report in LaTeX which involves a few tables. I'm stuck on that as my cell data in the table is exceeding the width of the page. Can I somehow wrap the text so that it falls into the next line in the same cell of the table?
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Is there ever a time where using a database 1:1 relationship makes sense?
...I would keep the demographic data regarding health coverage in a different table to both give easier security partitioning and to avoid hauling that data around in queries unrelated to insurance.
An example of a physical partition would be the same data being hosted on multiple servers. I may keep ...
@UniqueConstraint annotation in Java
...@UniqueConstraint annotation is for annotating multiple unique keys at the table level, which is why you get an error when applying it to a field.
References (JPA TopLink):
@UniqueConstraint
@Column
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How to delete from multiple tables in MySQL?
I am trying to delete from a few tables at once. I've done a bit of research, and came up with this
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Copy rows from one Datatable to another DataTable?
How can I copy specific rows from DataTable to another Datable in c#? There will be more than one row.
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Fastest way to replace NAs in a large data.table
I have a large data.table , with many missing values scattered throughout its ~200k rows and 200 columns. I would like to re code those NA values to zeros as efficiently as possible.
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How do I drop a foreign key constraint only if it exists in sql server?
I can drop a table if it exists using the following code but do not know how to do the same with a constraint:
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jquery UI Sortable with table and tr width
I am using jQuery UI sortable to make my table grid sortable. The code seems to work fine but because I am not adding width to td s, when I drag the tr it shrinks the content.
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