Conversion functions#
Trino will implicitly convert numeric and character values to the correct type if such a conversion is possible. Trino will not convert between character and numeric types. For example, a query that expects a varchar will not automatically convert a bigint value to an equivalent varchar.
When necessary, values can be explicitly cast to a particular type.
Conversion functions#
- cast(value AS type) type #
Explicitly cast a value as a type. This can be used to cast a varchar to a numeric value type and vice versa.
Formatting#
- format(format, args...) varchar #
Returns a formatted string using the specified format string and arguments:
SELECT format('%s%%', 123); -- '123%' SELECT format('%.5f', pi()); -- '3.14159' SELECT format('%03d', 8); -- '008' SELECT format('%,.2f', 1234567.89); -- '1,234,567.89' SELECT format('%-7s,%7s', 'hello', 'world'); -- 'hello , world' SELECT format('%2$s %3$s %1$s', 'a', 'b', 'c'); -- 'b c a' SELECT format('%1$tA, %1$tB %1$te, %1$tY', date '2006-07-04'); -- 'Tuesday, July 4, 2006'
- format_number(number) varchar #
Returns a formatted string using a unit symbol:
SELECT format_number(123456); -- '123K' SELECT format_number(1000000); -- '1M'
Data size#
The parse_data_size
function supports the following units:
Unit |
Description |
Value |
---|---|---|
|
Bytes |
1 |
|
Kilobytes |
1024 |
|
Megabytes |
10242 |
|
Gigabytes |
10243 |
|
Terabytes |
10244 |
|
Petabytes |
10245 |
|
Exabytes |
10246 |
|
Zettabytes |
10247 |
|
Yottabytes |
10248 |
- parse_data_size(string)#
Parses
string
of formatvalue unit
into a number, wherevalue
is the fractional number ofunit
values:SELECT parse_data_size('1B'); -- 1 SELECT parse_data_size('1kB'); -- 1024 SELECT parse_data_size('1MB'); -- 1048576 SELECT parse_data_size('2.3MB'); -- 2411724
Miscellaneous#
- typeof(expr) varchar #
Returns the name of the type of the provided expression:
SELECT typeof(123); -- integer SELECT typeof('cat'); -- varchar(3) SELECT typeof(cos(2) + 1.5); -- double