MaxCompute:HEX

string hex(<number>)

create table if not exists mf_math_fun_t(
     int_data     int,
     bigint_data  bigint,
     double_data  double,
     decimal_data decimal,
     float_data   float,
     string_data  string
    );
insert into mf_math_fun_t values
(null, -10, 0.525, 0.525BD, cast(0.525 as float), '10'),
(-20, null, -0.1, -0.1BD, cast(-0.1 as float), '-10'),
(0, -1, null, 20.45BD, cast(-1 as float), '30'),
(-40, 4, 0.89, null, cast(0.89 as float), '-30'),
(5, -50, -1, -1BD, null, '50'),
(-60, 6, 1.5, 1.5BD, cast(1.5 as float), '-50'),
(-1, -70, -7.5, -7.5BD, cast(-7.5 as float),null ),
(-80, 1, -10.2, -10.2BD, cast(-10.2 as float), '-1' ),
(9, -90, 2.58, 2.58BD, cast(2.58 as float), '0'),
(-100, 10, -5.8, -5.8BD, cast(-5.8 as float), '-90');

select * from mf_math_fun_t;
-- The following result is returned:
+------------+-------------+-------------+--------------+------------+-------------+
| int_data   | bigint_data | double_data | decimal_data | float_data | string_data |
+------------+-------------+-------------+--------------+------------+-------------+
| NULL       | -10         | 0.525       | 0.525        | 0.525      | 10          |
| -20        | NULL        | -0.1        | -0.1         | -0.1       | -10         |
| 0          | -1          | NULL        | 20.45        | -1.0       | 30          |
| -40        | 4           | 0.89        | NULL         | 0.89       | -30         |
| 5          | -50         | -1.0        | -1           | NULL       | 50          |
| -60        | 6           | 1.5         | 1.5          | 1.5        | -50         |
| -1         | -70         | -7.5        | -7.5         | -7.5       | NULL        |
| -80        | 1           | -10.2       | -10.2        | -10.2      | -1          |
| 9          | -90         | 2.58        | 2.58         | 2.58       | 0           |
| -100       | 10          | -5.8        | -5.8         | -5.8       | -90         |
+------------+-------------+-------------+--------------+------------+-------------+

Statik değerler

-- Integer input: returns the hex representation of the numeric value
select hex(17);
-- Returns: 11

select hex(0);
-- Returns: 0

-- String input: returns the hex encoding of the UTF-8 bytes
select hex('abc');
-- Returns: 616263

select hex('17');
-- Returns: 3137

-- Null input returns an error
select hex(null);
-- An error is returned.

Tamsayı ve dize girişleri farklı sonuçlar üretir. hex(17) ifadesi 17 sayısını onaltılık sisteme dönüştürür ( 11 ), oysa hex('17') ifadesi '1' ve '7' dize karakterlerini bayt olarak kodlar ( 3137 ).

Tablo verileri

Aşağıdaki örnekte, mf_math_fun_t örnek tablosu kullanılarak tüm sayısal sütunlar onaltılık sisteme dönüştürülür.

Bu sorguyu çalıştırmadan önce MaxCompute V2.0 veri türü sürümünü etkinleştirin.

set odps.sql.type.system.odps2=true;
select
  hex(int_data)     as int_new,
  hex(bigint_data)  as bigint_new,
  hex(double_data)  as double_new,
  hex(decimal_data) as decimal_new,
  hex(float_data)   as float_new,
  hex(string_data)  as string_new
from mf_math_fun_t;

Sonuç:

+------------------+------------------+------------+-------------+------------+------------+
| int_new          | bigint_new       | double_new | decimal_new | float_new  | string_new |
+------------------+------------------+------------+-------------+------------+------------+
| NULL             | FFFFFFFFFFFFFFF6 | 302E353235 | 302E353235  | 302E353235 | 3130       |
| FFFFFFFFFFFFFFEC | NULL             | 2D302E31   | 2D302E31    | 2D302E31   | 2D3130     |
| 0                | FFFFFFFFFFFFFFFF | NULL       | 32302E3435  | 2D31       | 3330       |
| FFFFFFFFFFFFFFD8 | 4                | 302E3839   | NULL        | 302E3839   | 2D3330     |
| 5                | FFFFFFFFFFFFFFCE | 2D312E30   | 2D31        | NULL       | 3530       |
| FFFFFFFFFFFFFFC4 | 6                | 312E35     | 312E35      | 312E35     | 2D3530     |
| FFFFFFFFFFFFFFFF | FFFFFFFFFFFFFFBA | 2D372E35   | 2D372E35    | 2D372E35   | NULL       |
| FFFFFFFFFFFFFFB0 | 1                | 2D31302E32 | 2D31302E32  | 2D31302E32 | 2D31       |
| 9                | FFFFFFFFFFFFFFA6 | 322E3538   | 322E3538    | 322E3538   | 30         |
| FFFFFFFFFFFFFF9C | A                | 2D352E38   | 2D352E38    | 2D352E38   | 2D3930     |
+------------------+------------------+------------+-------------+------------+------------+

Negatif tamsayılar (örneğin BIGINT olarak depolanan -10), ikiye tümleyen onaltılık gösterimlerini (FFFFFFFFFFFFFFF6) döndürür. DOUBLE, FLOAT ve DECIMAL değerleri, IEEE 754 bit düzenleri olarak değil, ondalık dize gösterimlerinin onaltılık kodlaması olarak işlenir.