SQLite equivalent of PostgreSQL's GREATEST function

user_37181 0
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PostgreSQL has a useful function called GREATEST. It returns the largest value of those passed to it as documented here.

Is there any equivalent in SQLite?

As a note, I only need it to work with 2 arguments.

postgresql sqlite sql
2 Answers

SELECT MAX(1,2,..)

ref: https://sqlite.org/lang_corefunc.html#maxoreunc

max(X,Y,...)

The multi-argument max() function returns the argument with the maximum value, or return NULL if any argument is NULL. The multi-argument max() function searches its arguments from left to right for an argument that defines a collating function and uses that collating function for all string comparisons. If none of the arguments to max() define a collating function, then the BINARY collating function is used. Note that max() is a simple function when it has 2 or more arguments but operates as an aggregate function if given only a single argument.

user_2597780

using a second value in MAX(value1, value2) would be the equivalent
Example:

UPDATE products SET Quantity = MAX(Quantity - @value, 0)...

if (Quantity - value) return a "Negative Number -0" then Max( , 0) will return 0
because 0 is bigger than -0 / -1 / -2 ... and so on
Max( , 1) will return 1 if the same condition (Quantity - value) return 0 or a Negative Number .. etc, you get the idea !

if we assume that both Quantity and @value could be NULL then use the combination: IFNULL(MAX(Quantity-@value,0),0)
IFNULL(..., 0) will return the second value of your choice IF the first one is NULL

user_74654520
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