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Why can't I use [LIMIT offset, row_count] in UPDATE query, just like I do it in SELECT statements? The manual says that the only right syntax for UPDATE is [LIMIT row_count], no offset. Is there any other way to do it? Thanks.

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why on earth would you need an offset?  when SELECTing, you need the offset to specify where in the resultset to start pulling; in an UPDATE, you're using the WHERE clause to explicitly state what rows you will or won't be updating.  the only use i could see for the offset in an UPDATE query is if you need to update an entire table and want to do it in chunks, but that's not even necessary - if they all need to be updated, you can just repeat the query several times with only the LIMIT row_count set.


in short, the order of SELECT matters, the order of UPDATE shouldn't, otherwise it isn't a legitimate UPDATE query.

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Here's an example. Let's say I have the following table:



|    10    |  36  |  0    |

|    11    |  64  |  1    |

|    12    |  52  |  1    |

|    13    |  36  |  1    |

|    14    |  36  |  0    |

|    15    |  28  |  0    |

|    16    |  36  |  1    |


Now I want to make the photo where photo_id=14 visible.

But all I have is the user_id (36) and the fact that I need to update his third photo in the table, I don't know the photo_id of the photo I want to update.

The question is how to achieve this using only one query.

Why can't I use use something like


UPDATE photos SET visible=1 WHERE user_id=36 LIMIT 3,1


It seems logical to me. I tried it with subqueries, it didn't work either.

Sorry if it all sounds stupid  :D

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I'm sorry, I don't see the problem here. You know the photo_id, so use it.


update photos

set visible=1

where photo_id=14


You should not need to limit an update at all, and if you do there is probably something wrong somewhere.

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