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SELECT 
  1 
FROM 
  vi_lock_keys 
WHERE 
  key_id = 'c4fbf20278066d92beedff0bc370e64b2ffe476a52cad84b38d2fdff6f450ec3' 
  AND token = 'dwXv/IWCZ2kiQU0SDdWWxklAtAEhO0pjGhe98P111gM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00009

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}