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Top Trading Days by Volume
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Top Trading Days by Volume

MediumSQL · PostgreSQL

Problem

Deutsche Börse Group wants to monitor peak activity on the Xetra trading venue. Write a PostgreSQL query that identifies the highest-volume trading day or days in each calendar month.

Requirements

  1. Join trades to instruments and include only trades for valid instruments.
  2. Consider only EXECUTED trades on Xetra with a non-null volume.
  3. Aggregate total volume by calendar month and trading date.
  4. Return every day tied for the highest volume in its month, using a window function. Sort by month and trading date.

Schema

trades
ColumnTypeDescription
trade_idPKINTEGERUnique trade identifier
instrument_idINTEGERReferenced instrument identifier
executed_atTIMESTAMPTimestamp when the trade was executed
volumeBIGINTNumber of units traded
trade_statusVARCHAR(20)Trade lifecycle status
venueVARCHAR(30)Trading venue
instruments
ColumnTypeDescription
instrument_idPKINTEGERUnique instrument identifier
symbolVARCHAR(20)Instrument trading symbol
product_nameVARCHAR(100)Instrument product name
asset_classVARCHAR(30)Instrument asset class
Tablestradesinstruments
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