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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b51853612f5e6f7078f6b13b1e7ce12cf07a86fd73820f38fba8c1d046a159a2' 
  AND token = '/U+N0mb5Bes0/hrwzrJnLWxT1VH2lIox9uyFO/BYwK0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00017

JSON explain

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