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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a68dcfd0a35bedceb1da4194ea1dd4aff6de9d63419dc7a2c00dc1f9acb21cb7' 
  AND token = 'HyR9W0Xv5FwMz3vy+DPrhQzfp+yf9sHN6IcTGmiuXKY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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