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MySQL date format DD/MM/YYYY select query?
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You can use STR_TO_DATE() to convert your strings to MySQL date values and ORDER BY the result:
ORDER BY STR_TO_DATE(datestring, '%d/%m/%Y')
However, you would be wise to convert the column to the DATE data type instead of using strings.
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Best data type for storing currency values in a MySQL database
What is the best SQL data type for currency values? I'm using MySQL but would prefer a database independent type.
9 Answer...
How to get the mysql table columns data type?
I want to get the column data type of a mysql table.
11 Answers
11
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MySQL Data - Best way to implement paging?
My iPhone app connects to my PHP web service to retrieve data from a MySQL database. A request can return 500 results.
7 An...
SQL Add foreign key to existing column
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MySQL / SQL Server / Oracle / MS Access:
ALTER TABLE Orders
ADD FOREIGN KEY (P_Id)
REFERENCES Persons(P_Id)
To allow naming of a FOREIGN KEY constraint, and for defining a FOREIGN KEY constraint on multiple columns, use th...
Are duplicate keys allowed in the definition of binary search trees?
...a BST which allows either of the right or left children to be equal to the root node, will require extra computational steps to finish a search where duplicate nodes are allowed.
It is best to utilize a list at the node to store duplicates, as inserting an '=' value to one side of a node requires r...
Select last row in MySQL
How can I SELECT the last row in a MySQL table?
10 Answers
10
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MySQL SELECT only not null values
...WHERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
Edited to reflect comments. It sounds like your table may not be in first ...
MySQL combine two columns into one column
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My guess is that you are using MySQL where the + operator does addition, along with silent conversion of the values to numbers. If a value does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two way...
How to use GROUP BY to concatenate strings in MySQL?
... id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string result with the concatenated non-NULL values from a group. It returns NULL if there ...