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Change MySQL default character set to UTF-8 in my.cnf?
...y.cnf settings worked for me as well. Additionally, I had to make sure the table was set properly, such as ALTER TABLE Table CONVERT TO CHARACTER SET utf8 COLLATE utf8_unicode_ci;
– Chris Livdahl
May 26 '11 at 19:26
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How does a Java HashMap handle different objects with the same hash code?
...n, (it might be slightly different from Java 6).
Data structures
Hash table
Hash value is calculated via hash() on key, and it decide which bucket of the hashtable to use for a given key.
Linked list (singly)
When count of elements in a bucket is small, a singly linked list is used.
Red-Black t...
Fast way of counting non-zero bits in positive integer
...se that.
To answer a question in the comments, for bytes I'd use a lookup table. You can generate it at runtime:
counts = bytes(bin(x).count("1") for x in range(256)) # py2: use bytearray
Or just define it literally:
counts = (b'\x00\x01\x01\x02\x01\x02\x02\x03\x01\x02\x02\x03\x02\x03\x03\x04'...
MySQL: determine which database is selected?
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DUAL is an Oracle table, that was taken over into MySQL. It's a dummy table for operations that do not require an actual table. en.wikipedia.org/wiki/DUAL_table
– Jan Thomä
Nov 11 '11 at 16:03
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Is there any good dynamic SQL builder library in Java? [closed]
... concept of code generation, where meta classes are generated for database tables and fields. This facilitates a nice, clean DSL but it faces a problem when trying to create queries for databases that are only known at runtime, like in the OP's example above. While jOOQ supports a String based appro...
How to hide first section header in UITableView (grouped style)
As the design of table views using the grouped style changed considerably with iOS 7, I would like to hide (or remove) the first section header. So far I haven't managed to achieve it.
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What are the disadvantages of using persistent connection in PDO
...tion die when the script terminates abnormally.
If the dead script locked tables, those tables will remain locked until the connection dies or the next script that gets the connection unlocks the tables itself.
If the dead script was in the middle of a transaction, that can block a multitude of ta...
How to make an inline-block element fill the remainder of the line?
...e using CSS and two inline-block (or whatever) DIV tags instead of using a table?
7 Answers
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Difference between Select Unique and Select Distinct
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Unique is a keyword used in the Create Table() directive to denote that a field will contain unique data, usually used for natural keys, foreign keys etc.
For example:
Create Table Employee(
Emp_PKey Int Identity(1, 1) Constraint PK_Employee_Emp_PKey Prim...
MySQL high CPU usage [closed]
... time, and use that to make sure you don't have any queries locking up key tables for too long.
Some other things you can check would be to run the following query while the CPU load is high:
SHOW PROCESSLIST;
This will show you any queries that are currently running or in the queue to run, what...