如何在同一列中查找和替换一列的值（Wordpress wp_postmeta 表）

Question

这是我的表格示例：

meta_id | post_id |  meta_key    | meta_value            
1       |  1001   |  Name        |  Jack                   
2       |  1002   |  Name        |  John                   
3       |  1001   |  Description |  Jack is 36 years old   
4       |  1002   |  Description |  John is Jack's brother

想在 meta_key 为“Description”的 meta_value 中找到 meta_key 为“Name”的 meta_value，并通过添加 post_id 来替换它。例如。在 meta_value 中搜索“Jack”，其中 meta_key 为“Description”，并将其替换为“Jack (post_id = 1001)”。

所以结果会是这样的：

meta_id | post_id |  meta_key    | meta_value            
1       |  1001   |  Name        | Jack                   
2       |  1002   |  Name        | John                   
3       |  1001   |  Description | Jack (post_id = 1001) is 36 years old   
4       |  1002   |  Description | John (post_id = 1002) is Jack (post_id = 1001)'s brother

只是让您知道该表有数百万条记录。任何帮助将不胜感激，干杯！

Answer 1

正如我在评论中所说，您必须遍历每个名​​称才能重新替换它。

当然你不能运行两次，所以我会创建一个新列并将结果放在那里。

第二个问题不是唯一的名字，例如某人只有名字 John，例程会替换它，但假设首先有一个 John Malkovitch，它已经被替换，然后 John 将被替换为不同的 id 两次。名字也不是唯一的 John Claude Smith 可能会退出数百次。算法无法区分它们。

DELIMITER $$
CREATE DEFINER=`root`@`localhost` PROCEDURE `procedure_name1`()
BEGIN
    DECLARE finished INTEGER DEFAULT 0;
    DECLARE _id INT DEFAULT 0;
    DECLARE _descrition TEXT DEFAULT "";
    DECLARE _descritionrep TEXT DEFAULT "";
    DECLARE _post_id INT DEFAULT 0;
    DECLARE _name TEXT DEFAULT ""; 
    -- declare cursor for DESCRITIOn
    DEClARE curnameexch 
        CURSOR FOR 
            SELECT `post_id`, `meta_value` FROM table2 WHERE `meta_key` = 'Name';

    DEClARE curdescritionexch 
        CURSOR FOR 
            SELECT `meta_id`,`meta_value` FROM table2 WHERE `meta_key` = 'Description';


    -- declare NOT FOUND handler
    DECLARE CONTINUE HANDLER 
        FOR NOT FOUND SET finished = 1;

    OPEN curdescritionexch;

    getdesiption: LOOP
        FETCH curdescritionexch INTO _id,_descrition;
        IF finished = 1 THEN 
            LEAVE getdesiption;
        END IF;
        -- build email list
        SET _descritionrep = _descrition;
            OPEN curnameexch;

            getname: LOOP
                FETCH curnameexch INTO _post_id,_name;
                IF finished = 1 THEN 
                    SET finished = 0;
                    LEAVE getname;
                END IF;
                -- build email list
                SET _descritionrep = REPLACE(_descritionrep,_name,
                      CONCAT(_name, ' (post_id = ',_post_id,')'));

            END LOOP getname;
            CLOSE curnameexch;
      --  aLL NAMES EXCHANGED
      UPDATE table2 set `meta_value` = _descritionrep 
      WHERE `meta_id` = _id; 
    END LOOP getdesiption;
    CLOSE curdescritionexch;
END$$
DELIMITER ;

Answer 2

/*
SELECT REPLACE(
  t1.meta_value, t.meta_value, CONCAT(t.meta_value, ' (post_id = ', t.post_id, ')'))
*/
UPDATE t1
FROM table t
LEFT JOIN table t1 ON t1.meta_key = 'Description' AND t.postId = t1.postId
SET meta_value := REPLACE(
  t1.meta_value, t.meta_value, CONCAT(t.meta_value, ' (post_id = ', t.post_id, ')'))
WHERE t.meta_key = 'Name'
;