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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):
8 Answers
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What's wrong with foreign keys?
...s
you can get nice "on delete cascade" behavior, automatically cleaning up tables
knowing about the relationships between tables in the database helps the Optimizer plan your queries for most efficient execution, since it is able to get better estimates on join cardinality.
FKs give a pretty big hi...
How do I catch a PHP fatal (`E_ERROR`) error?
...ace = print_r( debug_backtrace( false ), true );
$content = "
<table>
<thead><th>Item</th><th>Description</th></thead>
<tbody>
<tr>
<th>Error</th>
<td><pre&...
Why malloc+memset is slower than calloc?
...n parts here: your program, the standard library, the kernel, and the page tables. You already know your program, so...
Memory allocators like malloc() and calloc() are mostly there to take small allocations (anything from 1 byte to 100s of KB) and group them into larger pools of memory. For exam...
String literals and escape characters in postgresql
Attempting to insert an escape character into a table results in a warning.
5 Answers
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It has a DefiningQuery but no InsertFunction element… err
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Well when a table is encountered without a PrimaryKey it is treated as a View.
And views show up in the EDMX file (open in an XML editor to see) in the StorageModel\EntitySet[n]\DefiningQuery element.
When you have a DefiningQuery the ...
Joining three tables using MySQL
I have three tables named
8 Answers
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What does ON [PRIMARY] mean?
...ult one, which is always created, and so the SQL you've given creates your table ON the PRIMARY file group.
See MSDN for the full syntax.
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Repeat table headers in print mode
Is it possible in CSS using a property inside an @page to say that table headers (th) should be repeated on every page if the table spreads over multiple pages?
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Best explanation for languages without null
...f why null is undesirable is that meaningless states should not be representable.
Suppose I'm modeling a door. It can be in one of three states: open, shut but unlocked, and shut and locked. Now I could model it along the lines of
class Door
private bool isShut
private bool isLocked
an...