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How to choose the id generation strategy when using JPA and Hibernate
...that are unique only when no other process is inserting data into the same table. Do not use in a cluster.
identity
supports identity columns in DB2, MySQL, MS SQL Server, Sybase and HypersonicSQL. The returned identifier is of type long, short or int.
sequence
uses a sequence in DB2, PostgreSQL, Or...
MacOSX homebrew mysql root password
... for root. Uninstalled and reinstalled with Homebrew. Fresh install, fresh tables but when I enter
20 Answers
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What is the fastest factorial function in JavaScript? [closed]
...proach make sure to convert to exponential before using the aforementioned table.
– David Scott Kirby
May 2 '14 at 20:36
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PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
...b hardly a legacy platform yet.
Here is a process for altering a database table column to convert TIMESTAMP to DATETIME. It starts with creating a temporary column:
# rename the old TIMESTAMP field
ALTER TABLE `myTable` CHANGE `myTimestamp` `temp_myTimestamp` int(11) NOT NULL;
# create a new DAT...
Are negative array indexes allowed in C?
...want to use negative indexes, I have used them in two contexts:
Having a table of combinatorial numbers that tells you comb[1][-1] = 0; you can always check indexes before accessing the table, but this way the code looks cleaner and executes faster.
Putting a centinel at the beginning of a table. ...
How do I check to see if a value is an integer in MySQL?
... matching the string to a regular expression. Simply do
select field from table where field REGEXP '^-?[0-9]+$';
this is reasonably fast. If your field is numeric, just test for
ceil(field) = field
instead.
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Apply style ONLY on IE
...l comment in your HTML:
<!--[if IE]>
<style>
.actual-form table {
width: 100%;
}
</style>
<![endif]-->
There are numerous hacks (e.g. the underscore hack) you can use that will allow you to target only IE within your stylesheet, but it gets very messy if y...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...h gives 31-lzcnt for non-zero inputs.)
There's unfortunately no way to portably take advantage of the various CLZ instructions on non-x86 platforms that do define the result for input=0 as 32 or 64 (according to the operand width). x86's lzcnt does that, too, while bsr produces a bit-index that th...
.NET HashTable Vs Dictionary - Can the Dictionary be as fast?
I am trying to figure out when and why to use a Dictionary or a HashTable. I have done a bit of a search on here and have found people talking about the generic advantages of the Dictionary which I totally agree with, which leads the boxing and unboxing advantage for a slight performance gain.
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Update date + one year in mysql
When I want setting numerical value +1 in mysql table, I use e.g.:
3 Answers
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