How to implement a table in JSON

Optimal script to access a value in a table from row and column keys.

Example with the following table, which records the rankings of F1 world championship for teams.

How to represent this table in a JSON file so that we can reach a result by giving the team name and year, thus achieving a sort of SQL query?

The most resources economical way is to establish a schema describing the headers of rows and columns, and then to declare a matrix corresponding to the complementary part of the table:

Schema:

var teams = [ "Ferrari" , "Mercedes", "Williams"]
var years = [ "2013", "2014", "2015"]

Matrix:

var results = [
 [ 3, 4, 2],
 [ 2, 1, 1],
 [ 9, 3, 3] 
]

Then a query is defined:

function request(team, year) {
  var t = teams.indexOf(team)
  var y = years.indexOf(year)
  return results[t][y];
}

var team = "Williams"
var year = "2014"
var rank = request(team, year)
document.write(team + " ranking in " + year+ " : " + rank)

Demonstration:

Changing a value makes use of the same principle with an assignment instead: results [x] [y] = value.
Adding a row or column is done simply with the push or splice method of Array.

It is also possible for large tables to optimize the access by building an index:

var iteams = {}
for(var i in teams) {
  iteams[teams[i]] = i
}

var iyears = {}
for(var i in years) {
  iyears[years[i]] = i
}

Then we make a query directly like that:

var r = results[iteams[team], iyears[year]]