MySQL内部联接查询语法错误 [英] MySQL Inner Join Query Syntax error

问题描述

我是MySQL的新手，无法弄清楚这里出了什么问题.我有两张桌子.左侧的表格称为锻炼".相关列为date(类型日期)和id(类型int).

I'm kind of a MySQL novice and can't figure out what is going wrong here. I have two tables. The left table is called Workouts. The relevant columns are date (type date) and id (type int).

右表称为Workout_locations(相关字段:workout_id type int, and location_id type int).

The right table is called Workout_locations (relevant fields: workout_id type int, and location_id type int).

联接字段为Workouts.id和Workout_locations.workout_id.

我要做的就是得到一个包含两列的表:date(来自Workouts)和location_id(来自Workout_locations).我只需要基于几个字段从Workouts表中提取记录(sql语句应该清楚这一点).

All I want to do is get a table of two columns: date (from Workouts), and location_id (from Workout_locations). I need to only pull records from the Workouts table based on a couple of fields (the sql statement should make this clear).

这是我的sql语法:

SELECT Workouts.date as date, Workout_locations.location_id as loc_id
FROM Workouts 
WHERE Workouts.pacegroup_id='9' AND (Workouts.date BETWEEN '2013-08-19' AND '2013-08-25') 
INNER JOIN Workout_locations ON Workouts.id=Workout_locations.workout_id"

但是我得到这个错误:

您的SQL语法有错误；检查手册 对应于您的MySQL服务器版本以使用正确的语法 'INNER JOIN Workout_locations ON附近 第1行的Workouts.id = Workout_locations.workout_id'

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 'INNER JOIN Workout_locations ON Workouts.id=Workout_locations.workout_id' at line 1

我希望对于有经验的人来说，这是一个非常容易发现的错误.有人可以看到吗?谢谢！

I'm hoping that this is a very easy error to spot for someone who is experienced with this. Can anyone see it? Thanks!

推荐答案

您的INNER JOIN应该在WHERE之前.我也不认为您需要在<的 c12>子句，但我怀疑这两种方式都会导致错误:

Your INNER JOIN should come before the WHERE. I also don't think you needed the parens around your BETWEEN clause, but I doubt that it'll cause an error either way:

SELECT Workouts.date as date, Workout_locations.location_id as loc_id 
FROM Workouts 
INNER JOIN Workout_locations ON Workouts.id=Workout_locations.workout_id
WHERE Workouts.pacegroup_id = '9' 
AND Workouts.date BETWEEN '2013-08-19' AND '2013-08-25';

此外，尽管他们从技术上使他们脱颖而出，但您应该避免使用日期"作为选定的列名(这是一个

Also, though they technically let you get away with it, you should avoid using "date" as a selected column name (it's a reserved word).

您还可以进行一些简化以使内容更易于阅读:

You could do a bit of streamlining as well to make things a bit easier to read:

SELECT Workouts.date AS wo_date, Workout_locations.location_id AS loc_id
FROM Workouts w
INNER JOIN Workout_locations l ON w.id = l.workout_id
WHERE w.pacegroup_id = '9'
AND w.date BETWEEN '2013-08-19' AND '2013-08-25';

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