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Surrogate vs. natural/business keys [closed]
...lled as such. It is nothing more than a NOT NULL UNIQUE constraint, and a table can have more than one.
If you use a surrogate key, you still want a business key to ensure uniqueness according to the business rules.
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PDO Prepared Inserts multiple rows in single query
... fields to create the ? placeholders to bind your parameters.
insert into table (fielda, fieldb, ... ) values (?,?...), (?,?...)....
That is basically how we want the insert statement to look like.
Now, the code:
function placeholders($text, $count=0, $separator=","){
$result = array();
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How can a LEFT OUTER JOIN return more records than exist in the left table?
I have a very basic LEFT OUTER JOIN to return all results from the left table and some additional information from a much bigger table. The left table contains 4935 records yet when I LEFT OUTER JOIN it to an additional table the record count is significantly larger.
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How can I find which tables reference a given table in Oracle SQL Developer?
In Oracle SQL Developer , if I'm viewing the information on a table, I can view the constraints, which let me see the foreign keys (and thus which tables are referenced by this table), and I can view the dependencies to see what packages and such reference the table. But I'm not sure how to find wh...
Smallest data URI image possible for a transparent image
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After playing around with different transparent GIFs, some are unstable and cause CSS glitches. For example, if you have an <img> and you use the tiniest transparent GIF possible, it works fine, however, if you then want your transparent GIF to have a background-image, then this is im...
SQL MAX of multiple columns?
...(VALUES (date1), (date2), (date3),...) AS value(v)) as [MaxDate]
FROM [YourTableName]
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Setting up foreign keys in phpMyAdmin?
I'm setting up a database using phpMyAdmin. I have two tables ( foo and bar ), indexed on their primary keys . I am trying to create a relational table ( foo_bar ) between them, using their primary keys as foreign keys.
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How are virtual functions and vtable implemented?
...ons in C++":
Whenever a program has a virtual function declared, a v - table is constructed for the class. The v-table consists of addresses to the virtual functions for classes that contain one or more virtual functions. The object of the class containing the virtual function contains a virtual...
How do I vertically align text in a div?
...solution.html
Article summary:
For a CSS 2 browser, one can use display:table/display:table-cell to center content.
A sample is also available at JSFiddle:
div { border:1px solid green;}
<div style="display: table; height: 400px; overflow: hidden;">
<div style="display: table-c...
SQL JOIN and different types of JOINs
... and right joins are similar, if you are not bothered which is the primary table the join is based on.
– Anup
Oct 12 '14 at 11:37
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