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SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '9a83d31e95920e0ad4591eb32c539a67448f770699e7aa120d521716508e99f7' 
  AND token = '6HPgiMo1wHChaU9GHincImFsYjJRmxUJO62cFPwu5F8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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