SQL / Bulk update date columns

update.sql

# SQL Methods to randomize and update Wordpress posts-dates at once

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# First method :
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SET @STARTDATE = "2021-01-01";
SET @SETDATE = "2021-04-01 00:00:00";

UPDATE `wp_posts` 
SET `post_date` = @SETDATE, `post_date_gmt` = @SETDATE, `post_modified` = @SETDATE, `post_modified_gmt` = @SETDATE
WHERE `post_date` >= @STARTDATE


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# Second method / advanced :
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SET @STARTDATE = "2021-01-01";
SET @MIN = "2021-04-01 00:00:00";
SET @MAX = "2021-04-30 12:34:18";

UPDATE `wp_posts`
SET `post_date` = TIMESTAMPADD(SECOND, FLOOR(RAND() * TIMESTAMPDIFF(SECOND, @MIN, @MAX)), @MIN),
`post_date_gmt` = TIMESTAMPADD(SECOND, FLOOR(RAND() * TIMESTAMPDIFF(SECOND, @MIN, @MAX)), @MIN),
`post_modified` = TIMESTAMPADD(SECOND, FLOOR(RAND() * TIMESTAMPDIFF(SECOND, @MIN, @MAX)), @MIN),
`post_modified_gmt` = TIMESTAMPADD(SECOND, FLOOR(RAND() * TIMESTAMPDIFF(SECOND, @MIN, @MAX)), @MIN)
WHERE `post_date` >= @STARTDATE