Starting migration: Add exchange column to crypto_market_autotrader_positions
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✓ Exchange column already exists

Positions with empty exchange: 0
✓ All positions already have exchange values

Checking index on exchange column...
✓ Index already exists

Exchange distribution in positions:
  - blofin: 1377 positions
  - papertrade: 405 positions
  - kraken: 286 positions
  - apex: 4 positions

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Migration completed successfully!