How Can I Efficiently Rearrange Multiple Records Based on a Single Update in SQL?

Making Changes to Multiple Records Based on a Single Record Update with SQL

In a database table containing a list of food items with a "Position" field representing their order on the list, the need often arises to rearrange their order based on changes to a single record. The query provided by the original poster involves a cumbersome multi-step process involving data extraction, manipulation in JavaScript, and multiple database updates.

However, a more efficient approach that resolves the issue with a single query is:

<code class="sql">UPDATE my_table SET position = position * 10;</code>

This query multiplies the position of all records in the table by 10, creating ample gaps between positions. Subsequently, a simple update to the target record to move "Pears" to the desired position can be easily achieved with the following query:

<code class="sql">UPDATE my_table SET position = 15 WHERE listId=1 AND name = 'Pears';</code>

To address any concerns about gaps disappearing over time due to subsequent reordering, the query provided earlier can be periodically executed to update positions and maintain the necessary spacing. Using this efficient single-query approach, rearranging the order of food items becomes a straightforward task.

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