mysql(5.6及以下及以下)解析解析json的方法实例详解的方法实例详解
mysql(5.6及以下)解析json
#json解析函数
DELIMITER $$
DROP FUNCTION IF EXISTS `json_extract_c`$$
CREATE FUNCTION `json_extract_c`(
details TEXT,
required_field VARCHAR (255)
) RETURNS TEXT CHARSET latin1
BEGIN
SET details = SUBSTRING_INDEX(details, "{", -1);
SET details = SUBSTRING_INDEX(details, "}", 1);
RETURN TRIM(
BOTH '"' FROM SUBSTRING_INDEX(
SUBSTRING_INDEX(
SUBSTRING_INDEX(
details,
CONCAT(
'"',
SUBSTRING_INDEX(required_field,'$.', -1),
'":'
),
-1
),
',"',
1
),
':',
-1
)
) ;
END$$
DELIMITER ;
example:
select json_extract_c(json, "$.totalDays"), json from item limit 100;
自测
CREATE TABLE `json_test` (
`id` int(11) DEFAULT NULL,
`person_desc` text COLLATE utf8mb4_unicode_ci
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci;
insert INTO json_test values(2,'{"firstName":"Sergei","lastName":"Rachmaninoff","instrument":"piano"}');
SELECT id,json_extract_c(person_desc,'$.lastName') as "keys" FROM json_test;
改进,再找不到key,返回”值,之前的是在找不到的情况下,查找到第一的值。
CREATE DEFINER=`zhangfen`@`%` FUNCTION `json_extract_c`(
details TEXT,
required_field VARCHAR (255)
) RETURNS text CHARSET latin1
BEGIN
SET details = SUBSTRING_INDEX(details, "{", -1);
SET details = SUBSTRING_INDEX(details, "}", 1);
RETURN TRIM(
BOTH '"' FROM SUBSTRING_INDEX(
SUBSTRING_INDEX(
SUBSTRING_INDEX(
CONCAT('"":"",',details),
CONCAT(
'"',
SUBSTRING_INDEX(required_field,'$.', -1),
'":'
),
-1
),
',"',
1
),
':',
-1
)
) ;
END
评论0