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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'b2e1b0b3f3fcbc730d99fdd487db4c0269d5bcf38a35bec4eb522c1ee1a9bfe0' 
  AND token = '8ubWQ7q7zn4yxjVObqJzfrXba9i8uLBic4OZF1O16ek=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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