UNCOMPRESS_FLOATS

📄字数 530

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功能描述

解压被压缩的浮点型数组数据，根据压缩函数 COMPRESS_FLOATS() 指定的精度自动确定解压精度。

语法格式

UNCOMPRESS_FLOATS(expr)

输入参数

• expr：需要解压的数据，BINARY 类型。

输出结果

返回 FLOAT[] 类型，任意参数为 NULL 时，输出结果为 NULL。

示例

SQL> CREATE TABLE tab_test_uncompress_float(c1 FLOAT[]);

SQL> INSERT INTO tab_test_uncompress_float VALUES('{12.34,1.34,-2.56}');

-- 解压数据，自动确定解压精度
SQL> SELECT UNCOMPRESS_FLOATS(COMPRESS_FLOATS(c1, 0)), UNCOMPRESS_FLOATS(COMPRESS_FLOATS(c1, 1)) FROM tab_test_uncompress_float;

+-----------+-----------------+
|   EXPR1   |      EXPR2      |
+-----------+-----------------+
| {-2,1,12} | {-2.5,1.3,12.3} |
+-----------+-----------------+

SQL> SELECT UNCOMPRESS_FLOATS(COMPRESS_FLOATS(c1, 2)), UNCOMPRESS_FLOATS(COMPRESS_FLOATS(c1, 3)) FROM tab_test_uncompress_float;

+--------------------+-----------------------------------+
|       EXPR1        |               EXPR2               |
+--------------------+-----------------------------------+
| {-2.56,1.34,12.34} | {-2.5585938,1.3398438,12.3359375} |
+--------------------+-----------------------------------+