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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'df152a5be2aa2df83eff2fb0ff8f1819d7c54ecfca90757f3b6ab3d67cb54d50' 
  AND token = '3GBB3sxL6yeO5+wSh5JsCZBj/rRm7TtkIMMl65t16E0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00027

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}