VarunVats9

Latency numbers every programmer should know

L1 cache reference ......................... 0.5 ns
Branch mispredict ............................ 5 ns
L2 cache reference ........................... 7 ns
Mutex lock/unlock ........................... 25 ns
Main memory reference ...................... 100 ns             
Compress 1K bytes with Zippy ............. 3,000 ns  =   3 µs
Send 2K bytes over 1 Gbps network ....... 20,000 ns  =  20 µs
SSD random read ........................ 150,000 ns  = 150 µs

Read 1 MB sequentially from memory ..... 250,000 ns = 250 µs

VarunVats9

// Filter
GET /bank/_search >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
{
  "query": {
    "bool": {
      "must": [
        {
          "match": {
            "lastname": "Smith"
          }

VarunVats9

// Inner hits, has_child query
GET /department/_search >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
{
  "query": {
    "has_child": {
      "type": "employee",
      "inner_hits": {},
      "query": {
        "bool": {
          "must": [

VarunVats9

// Mapping
PUT /departments >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
{
  "mappings": {  
    "properties": {
      "name": {
        "type": "text"
      },
      "employees": {
        "type": "nested"

VarunVats9

// Mapping
PUT /department >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
{
  "mappings": {
    "properties": {
      "join_field": { 
        "type": "join",
        "relations": {
          "department": "employee"
        }

VarunVats9

// Elasticsearch API
https://www.elastic.co/guide/en/elasticsearch/reference/current/docs.html

// Typeless API
https://www.elastic.co/blog/moving-from-types-to-typeless-apis-in-elasticsearch-7-0

// Mapping  >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
PUT /product
{
  "mappings": {

VarunVats9

// MATCH == SHOULD
GET /product/_search >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
{
  "query": {
    "match": {
      "name": "Spring Title"
    }
  }
}

VarunVats9

// Add another field
PUT /product/_mapping >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
{
  "properties": {
    "date": {
      "type": "date",
      "format": "yyyy-MM-dd"
    }
  }
}

VarunVats9

// Term queries don't analyze the query, just search for the exact term in the inverted index >>>>>>>>>
  "query": {
    "term": {
      "name": "Framework"
    }
  }
}

GET /product/_search
{

VarunVats9

Reference:
https://opensourceconnections.com/blog/2013/07/24/understanding-how-cql3-maps-to-cassandras-internal-data-structure-sets-lists-and-maps/


// Column-Family
-----------------------------------------------------------------------------------------------
ID         Last    First   Bonus
 1          Doe     John    8000
 2          Smith   Jane    4000
 3          Beck    Sam     1000