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Primary key or Unique index?
...ork we have a big database with unique indexes instead of primary keys and all works fine.
15 Answers
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How can I be notified when an element is added to the page?
...t being inserted here,
// or a particular node being modified
// call the function again after 100 milliseconds
setTimeout( checkDOMChange, 100 );
}
Once this function is called, it will run every 100 milliseconds, which is 1/10 (one tenth) of a second. Unless you need real-time elemen...
How to create id with AUTO_INCREMENT on Oracle?
...NCREMENT by 1),
c2 VARCHAR2(10)
);
Alternatively, Oracle 12 also allows to use a sequence as a default value:
CREATE SEQUENCE dept_seq START WITH 1;
CREATE TABLE departments (
ID NUMBER(10) DEFAULT dept_seq.nextval NOT NULL,
DESCRIPTION VARCHAR2(50) NOT NULL);
ALTER T...
Is a Java string really immutable?
We all know that String is immutable in Java, but check the following code:
15 Answers
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Which MySQL data type to use for storing boolean values
...'N' or 'T'/'F' etc. depending upon the context. The advantage of using a small integer type is that you get maximum portability across RDBMS-es
– Roland Bouman
May 15 '10 at 22:42
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Performance of Java matrix math libraries? [closed]
....
Using Jama with Java, the time taken was 50 seconds.
Using Colt and Parallel Colt with Java, the time taken was 150 seconds!
Using JBLAS with Java, the time taken was again around 4 seconds as JBLAS uses multithreaded ATLAS.
So for me it was clear that the Java libraries didn't perform too wel...
Performing regex Queries with pymongo
... :
db.collectionname.find({'files':{'$regex':'^File'}})
This will match all documents that have a files property that has a item within that starts with File
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How to Right-align flex item?
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Thanks. Would you personally prefer this over Yohann Tilotti's display table method above? If so, why?
– Mark Boulder
Mar 16 '14 at 4:19
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Is SecureRandom thread safe?
... initializing a SecureRandom can not only be slow, but can potentially hang because of missing entropy
– Walter Tross
Jul 25 '14 at 9:37
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How do I move a Git branch out into its own repository?
...have a branch that I'd like to move into a separate Git repository, and ideally keep that branch's history in the process. So far I've been looking at git filter-branch , but I can't make out whether it can do what I want to do.
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