json解析函数

palo目前支持3个json解析函数

  • get_json_int（string，string）

  • get_json_string（string，string）

  • get_json_double（string，string）

其中第一个参数为json字符串，第二个参数为json内的路径

举例：

  1. mysql> select get_json_int('{"col1":100, "col2":"string", "col3":1.5}', "$.col1");
  2. +---------------------------------------------------------------------+
  3. | get_json_int('{"col1":100, "col2":"string", "col3":1.5}', '$.col1') |
  4. +---------------------------------------------------------------------+
  5. |                                                                 100 |
  6. +---------------------------------------------------------------------+
  7. 1 row in set (0.01 sec)
  1. mysql> select get_json_string('{"col1":100, "col2":"string", "col3":1.5}', "$.col2");
  2. +------------------------------------------------------------------------+
  3. | get_json_string('{"col1":100, "col2":"string", "col3":1.5}', '$.col2') |
  4. +------------------------------------------------------------------------+
  5. | string                                                                 |
  6. +------------------------------------------------------------------------+
  7. 1 row in set (0.01 sec)
  1. mysql> select get_json_double('{"col1":100, "col2":"string", "col3":1.5}', "$.col3");
  2. +------------------------------------------------------------------------+
  3. | get_json_double('{"col1":100, "col2":"string", "col3":1.5}', '$.col3') |
  4. +------------------------------------------------------------------------+
  5. |                                                                    1.5 |
  6. +------------------------------------------------------------------------+
  7. 1 row in set (0.01 sec)