Difference between revisions of "Maximum"
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<div class="ecomm e-mysql" style="display: none">In MySQL you can also use the <code>GREATEST</code> or <code>LEAST</code> functions to do this.</div> | <div class="ecomm e-mysql" style="display: none">In MySQL you can also use the <code>GREATEST</code> or <code>LEAST</code> functions to do this.</div> | ||
<div class="ecomm e-oracle" style="display: none">In Oracle you can also use the <code>GREATEST</code> or <code>LEAST</code> functions to do this.</div> | <div class="ecomm e-oracle" style="display: none">In Oracle you can also use the <code>GREATEST</code> or <code>LEAST</code> functions to do this.</div> | ||
| + | </div> | ||
{{Hacks Ref}} | {{Hacks Ref}} | ||
Revision as of 14:06, 30 July 2012
Calculate the maximum or minimum of two fields
DROP TABLE t
CREATE TABLE t( id VARCHAR(10), x INTEGER, y INTEGER ); INSERT INTO t VALUES ('A',1,2); INSERT INTO t VALUES ('B',4,3); INSERT INTO t VALUES ('C',5,5);
The function for using MAX over two fields is
max(x,y) = (x + y + ABS(x-y))/2
The function for using MIN over two fields is
min(x,y) = (x + y - ABS(x-y))/2
SELECT id, x, y, (x+y+ABS(x-y))/2 FROM t
Hack 10 Converting subqueries into joins
Hack 11 Converting aggregate subqueries into joins
Hack 16 Search for a String across columns
Hack 24 Multiply Across a Result Set
Hack 25.5 Splitting and combining columns
Hack 26 Include the rows your JOIN forgot
Hack 30 Calculate the maximum/minimum of two fields
Hack 33 Get values and subtotals in one shot
Hack 50 Combine tables containing different data
Hack 51/52 Display rows as columns
Hack 55 Import Someone Else's Data
Hack 62 Issue Queries Without Using a Table
Hack 63 Generate rows without tables
Hack 72 Extract a subset of the results
Hack 78 Break it down by Range
Hack 88 Test two values from a subquery
