数据脱敏之SHA脱敏

SHA 脱敏对字符列起作用，对列内容应用 SHA 算法处理。

示例：

gbase> CREATE TABLE t_m_sha(context VARCHAR(255) MASKED WITH(FUNCTION = 'SHA()'));
Query OK, 0 rows affected (Elapsed: 00:00:00.08)
gbase> INSERT INTO t_m_sha VALUES('abc');
Query OK, 1 row affected (Elapsed: 00:00:00.10)
gbase> SELECT * FROM t_m_sha;
+------------------------------------------+
| context                                  |
+------------------------------------------+
| a9993e364706816aba3e25717850c26c9cd0d89d |
+------------------------------------------+
1 row in set (Elapsed: 00:00:00.03)