TOLOWER - MaxCompute - Alibaba Cloud Documentation Center

Converts uppercase letters in a string specified by source into lowercase letters.

Syntax

string tolower(string <source>)

Parameters

source: required. A value of the STRING type. If the input value is of the BIGINT, DOUBLE, DECIMAL, or DATETIME type, the value is implicitly converted into a value of the STRING type before calculation. Only English characters are supported.

Return value

A value of the STRING type is returned. The return value varies based on the following rules:

If the value of source is not of the STRING, BIGINT, DOUBLE, DECIMAL, or DATETIME type, an error is returned.
If the value of source is null, null is returned.

Examples

Example 1: Convert uppercase letters in a string into lowercase letters. Sample statement:

-- The return value is abcd. 
select tolower('aBcd');
-- The return value is china fighting. 
select tolower('China Fighting');

Example 2: The input parameter is set to null. Sample statement:
```
-- The return value is null. 
select tolower(null);
```

Related functions

TOLOWER is a string function. For more information about functions related to string searches and conversion, see String functions.