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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 ...
Alter a MySQL column to be AUTO_INCREMENT
...ber between parenthesis does exactly nothing (well ok, almost nothing) for MySQL integer types. The only thing that may be influenced by the number is the display width, and it is up to the client to do that. But don't be deceived and think that it works like it does for VARCHAR and DECIMAL types - ...
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...
What does it mean when MySQL is in the state “Sending data”?
What does it mean if the Mysql query:
2 Answers
2
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MySQL Like multiple values
I have this MySQL query.
9 Answers
9
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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...
Drop all tables whose names begin with a certain string
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MYSQL: SELECT concat('DROP TABLE ',TABLE_NAME,";") as data FROM INFORMATION_SCHEMA.TABLES WHERE TABLE_NAME LIKE '[prefix]%' --- for those who like me found this thread
– Andre
Nov 6 '12...