title: Query from secondary index on aerospike
body: <p>I'm considering aerospike for one of our projects. So I currently created a 3 node cluster and loaded some data on it.</p>
  
  <p>Sample data </p>
  
  <p>ns: imei</p>
  
  <p>set: imei_data</p>
  
  <pre><code>+-------------------+-----------------------+-----------------------+----------------------------+--------------+--------------+
  | imsi              | fcheck                | lcheck                | msc                        | fcheck_epoch | lcheck_epoch |
  +-------------------+-----------------------+-----------------------+----------------------------+--------------+--------------+
  | "413010324064956" | "2017-03-01 14:30:26" | "2017-03-01 14:35:30" | "13d20b080011044917004100" | 1488358826   | 1488359130   |
  | "413012628090023" | "2016-09-21 10:06:49" | "2017-09-16 13:54:40" | "13dc0b080011044917006100" | 1474432609   | 1505550280   |
  | "413010130130320" | "2016-12-29 22:05:07" | "2017-10-09 16:17:10" | "13d20b080011044917003100" | 1483029307   | 1507546030   |
  | "413011330114274" | "2016-09-06 01:48:06" | "2017-10-09 11:53:41" | "13d20b080011044917003100" | 1473106686   | 1507530221   |
  | "413012629781993" | "2017-08-16 16:03:01" | "2017-09-13 18:10:48" | "13dc0b080011044917004100" | 1502879581   | 1505306448   |
  </code></pre>
  
  <p>Then I created a secondary index on lcheck_epoch using AQL since I want to query based on date.</p>
  
  <p><code>create index idx_lcheck on imei.imei_data (lcheck_epoch) NUMERIC</code></p>
  
  <pre><code>+--------+----------------+-----------+-------------+-------+--------------+----------------+-----------+
  | ns     | bin            | indextype | set         | state | indexname    | path           | type      |
  +--------+----------------+-----------+-------------+-------+--------------+----------------+-----------+
  | "imei" | "lcheck_epoch" | "NONE"    | "imei_data" | "RW"  | "idx_lcheck" | "lcheck_epoch" | "NUMERIC" |
  +--------+----------------+-----------+-------------+-------+--------------+----------------+-----------+
  </code></pre>
  
  <p>When I execute </p>
  
  <p><code>select imsi from imei.imei_data where idx_lcheck=1476165806</code></p>
  
  <p>I'm getting </p>
  
  <p><code>Error: (204) AEROSPIKE_ERR_INDEX</code></p>
  
  <p>Please explain.</p>