# Script Syntax

In edql we can define variable to control the context logics, if we need to query multi indexes with the same query conditions, we can use variable as a Query DSL Block for these multiple actions, example:

function extractCodes() {
  POST my-index/_search
  {
    "size": 0,
    "aggs": {
      "t": {
        "terms": {
          "field": "title.keyword"
        }
      }
    }
  }
}
var p = jq(extractCodes(), "$.aggregations.t.buckets[*].key")
for (i in $p) {
  POST my-index/_search
  {
    "query": {
      "bool": {
        "must": [
          {
            "term": {
              "title.keyword": $i
            }
          }
        ]
      }
    },
  }
}

we define p variable for title keywords and extract it as array by jq, in for loop we iterate all keywords

Function is used to abstract the common logics and for building custom library for your own projects. such as data dictionary, common query logics for quickly query data and locate data issues.

System Function is edql already defined functions for supporting file IO etc. example:

• readJSON

  local p = readJSON("filename")
  

  read json file from file path

• writeJSON

  writeJSON($p, "filename")
  

  write variable to file path

• jq

  jq({"name": "edql"}, "$.name")
  

  used to extract json value as json type variable

• TODO readExcel

• TODO writeExcel

Define Function this is for user abstract common query logics, example:

function extractCodes() {
  POST my-index/_search
  {
    "size": 0,
    "aggs": {
      "t": {
        "terms": {
          "field": "title.keyword"
        }
      }
    }
  }
}

quickly aggregation current my index title keywords

import keyword is used to import other edql script as a library, we use this feature to design or create default functions. for import, there are two path could be used

import "library.edql"
import "https://raw.github.io/xxx"

EDQL will find import script by absolute path to load import file.

EDQL will load import script from GitHub when using an HTTP url in import

EDQL supports an iterated collection by for loop, so in some times we want query results from a collection, it's easy to achieve this

for(a in [1, 2]) {
  echo a
}

comment in edql script by using #

#mycomment