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Mysql order by specific ID values
...and FIELD function.
See http://lists.mysql.com/mysql/209784
SELECT * FROM table ORDER BY FIELD(ID,1,5,4,3)
It uses Field() function, Which "Returns the index (position) of str in the str1, str2, str3, ... list. Returns 0 if str is not found" according to the documentation. So actually you sort th...
Removing a list of characters in string
...was changed and now takes 1 parameter instead of 2.
That parameter is a table (can be dictionary) where each key is the Unicode ordinal (int) of the character to find and the value is the replacement (can be either a Unicode ordinal or a string to map the key to).
Here is a usage example:
>&...
Oracle “Partition By” Keyword
...ment for every employee record. (It is as if you're de-nomalising the emp table; you still return every record in the emp table.)
emp_no dept_no DEPT_COUNT
1 10 3
2 10 3
3 10 3 <- three because there are three "dept_no = 10" records
4 20 2
5 ...
How can bcrypt have built-in salts?
...k. It's meant to prevent an attacker with read-only access to the password table from authenticating. For example, you get a backup tape with the table on it.
– erickson
Aug 6 '14 at 22:38
...
Join vs. sub-query
...and query-specific.
Historically, explicit joins usually win, hence the established wisdom that joins are better, but optimisers are getting better all the time, and so I prefer to write queries first in a logically coherent way, and then restructure if performance constraints warrant this.
...
What, exactly, is needed for “margin: 0 auto;” to work?
...y head:
The element must be block-level, e.g. display: block or display: table
The element must not float
The element must not have a fixed or absolute position1
Off the top of other people's heads:
The element must have a width that is not auto2
Note that all of these conditions must be tru...
Number of rows affected by an UPDATE in PL/SQL
...s with the number of line affected by the last DML operation:
say we have table CLIENT
create table client (
val_cli integer
,status varchar2(10)
)
/
We would test it this way:
begin
dbms_output.put_line('Value when entering the block:'||sql%rowcount);
insert into client
se...
sql server invalid object name - but tables are listed in SSMS tables list
.... However the SSMS intellisense does not recognize more than half of the tables which have been created.
16 Answers
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UIRefreshControl - beginRefreshing not working when UITableViewController is inside UINavigationCont
I've setup a UIRefreshControl in my UITableViewController (which is inside a UINavigationController) and it works as expected (i.e. pull down fires the correct event). However, if I programmatically invoke the beginRefreshing instance method on the refresh control like:
...
How can I find non-ASCII characters in MySQL?
... but I would suggest trying a variant of a query like this:
SELECT * FROM tableName WHERE columnToCheck NOT REGEXP '[A-Za-z0-9]';
That query will return all rows where columnToCheck contains any non-alphanumeric characters. If you have other characters that are acceptable, add them to the charact...