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max aggregate function

Applies to: check marked yes Databricks SQL check marked yes Databricks Runtime

Returns the maximum value of expr in a group.

Syntax

max(expr) [FILTER ( WHERE cond ) ]

This function can also be invoked as a window function using the OVER clause.

Arguments

  • expr: An expression of any type that can be ordered.
  • cond: An optional boolean expression filtering the rows used for aggregation.

Returns

The result type matches the type of the argument.

Note

For certain STRING collations, such as UTF8_LCASE, the result may be non-deterministic.

Examples

> SELECT max(col) FROM VALUES (10), (50), (20) AS tab(col);
 50

-- The result is non-deterministic due to collation
> SELECT max(col COLLATE UTF8_LCASE) FROM VALUES ('a', 'A') AS tab(col);
 a (or A)