Correcting Swapped Sequences in Delivery Logs

Correcting Swapped Sequences in Delivery Logs

A delivery platform experienced a technical glitch where every pair of consecutive items in their order logs was swapped (i.e., the item intended for ID 1 was recorded for ID 2, and vice versa). You are given a table orders with columns order_id (unique, sequential integers starting from 1) and item (the name of the food). Write a query to restore the correct mapping. If the total number of orders is odd, the final order ID should remain paired with its original item. The output should be sorted by order_id in ascending order.
PostgreSQLCTEWindow FunctionLEADLAG
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