I am trying to re-write this mysql query in SQLAlchemy:
Schema:
CREATE TABLE `posts` (
`post_id` INT UNSIGNED PRIMARY AUTO_INCREMENT,
`post_name` VARCHAR(255)
) Engine=InnoDB;
CREATE TABLE `post_tags` (
`tag_id` INT UNSIGNED PRIMARY AUTO_INCREMENT,
`tag_name` VARCHAR(255)
) Engine=InnoDB;
CREATE TABLE `post_tags_map` (
`map_id` INT PRIMARY AUTO_INCREMENT,
`post_id` INT NOT NULL,
`tags_id` INT NOT NULL,
FOREIGN KEY `post_id` REFERENCES `posts` (`post_id`),
FOREIGN KEY `post_id` REFERENCES `post_tags` (`tag_id`)
) Engine=InnoDB;
Query:
SELECT
posts.*,
GROUP_CONCAT( post_tags.tag_name order by post_tags.tag_name ) AS tags
FROM posts
LEFT JOIN posts_tags_map
ON posts_tags_map.post_id = posts.post_id
LEFT JOIN post_tags
ON posts_tags_map.tags_id = posts_tags.tag_id
WHERE posts.post_id = 1
GROUP BY post_id
Here's what I have, but I keep getting:
1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'SEPARATOR /))
rows = DBSession.query(Posts,func.group_concat(Post_Tags.tag_name.op('SEPARATOR')(literal_column('/')))).outerjoin(PostsTagsMap,Posts.post_id==PostsTagsMap.post_id).outerjoin(Post_Tags,PostsTagsMap.tags_id==Post_Tags.tag_id).group_by(Posts.post_id)
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