Some memory aids for me so that I don't have to keep looking them up:

MySQLT-SQL
Strings
String ReplaceREPLACE(haystack,needle,replacement)REPLACE(haystack,needle,replacement)
String PositionINSTR(haystack, needle)
LOCATE(needle, haystack [, offset])
PATINDEX(%needle%, haystack)
CHARINDEX(needle, haystack [, offset])
String ConcatenationCONCAT(string1,string2[,stringN])string1 + string2
SS v2012+:
CONCAT(string1, string2 [, stringN ])
String SubstringSUBSTRING( string,start,length )SUBSTRING( string,start,length )
String LengthLENGTH(string)
BIT_LENGTH(string)
CHAR_LENGTH(string)
LEN(string)
DATALENGTH(string)
Dates / Times
Weekday NameDAYNAME(now())DATENAME(dd, getdate())
Weekday NumberDAYOFWEEK(now())DATEPART(dw, getdate())
Month NameMONTHNAME(now())DATENAME(mm, getdate())
Month NumberMONTH(now())DATEPART(mm, getdate())
European Date (dd/mm/yyyy)DATE_FORMAT(now(), '%d/%m/%Y')CONVERT(varchar, getdate(), 103)
Time to SecondsTIME_TO_SEC(now())(DATEPART(hour, getdate()) * 3600) +
(DATEPART(minute, getdate()) * 60) +
(DATEPART(second, getdate()))
Seconds to TimeSEC_TO_TIME( seconds )CONVERT(varchar, DATEADD(ms, seconds * 1000, 0), 114)
Add/Subtract DateDATE_ADD(date,INTERVAL number datepart)
DATE_SUB(date,INTERVAL number datepart)
DATEADD(datepart, number, date)
DATESUB(datepart, number, date)
Other
If-then-elseIF( expression,value_if_true,value_if_false )IIF( expression,value_if_true,value_if_false )
If NullIFNULL(column_name,value_if_null)ISNULL(column_name,value_if_null)
Rank/Rownum (@rownum:=@rownum+1) AS Rownum
LIMIT from_index, number_of_rows
ROW_NUMBER() OVER(ORDER BY column_name ASC) AS Rownum


Source(s):

What?
So this is a quick article on how to install the mySQL add-on for Oracle SQL Developer v3.0.04.

Why?
I've used various mySQL administration tools to manage mySQL databases over the years, all freeware until someone expresses an interest in using it and then the supplier will implement restrictions and trial based versions. Oracle SQL Developer is currently free at time of print (01-FEB-2013).

I also need to use Oracle databases in my day job so the Oracle SQL developer is already a pre-approved software for our work computers. We have SQL Server Management Studio (SSMS) as well for our SQL Server instances but it wasn't practical to link this to mySQL databases.

How?

What?
In view of the fact that this error pops up in so many systems I take over, I have often gone down the wrong path following the red herring as it were when in fact the answer to this is very common.

Why?
Bespoke systems are the usual suspects. Developers will have told the system what to do when newline, carriage returns and tab characters are entered in the data. Those who are security-conscious will also make their system escape apostrophes (') and double-quotes ("). But who can honestly build a system that thinks of everything from day one?

How?

MySQL is just the best
Unfortunately I make a living using Microsoft and Oracle products. I shouldn't say unfortunately as I don't see myself doing any other job and it beats daytime television any day.

I use this quite a lot so I thought I'd put an article here somewhere. Based on the following concept:

RowID     column_to_return_as_string   
--------- --------------------------
1         Me
2         Myself
3         I

-- to be returned as
RowID     my_field_name   
--------- --------------------------
1         Me,Myself,I

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