Files
Windshaft-cartodb/lib/cartodb/models/dataview/overviews/formula.js
T

57 lines
1.9 KiB
JavaScript

var BaseOverviewsDataview = require('./base');
var BaseDataview = require('../formula');
var dot = require('dot');
dot.templateSettings.strip = false;
var formulaQueryTpls = {
'count': dot.template([
'SELECT',
'sum(_feature_count) AS result,',
'(SELECT count(1) FROM ({{=it._query}}) _cdb_formula_nulls WHERE {{=it._column}} IS NULL) AS nulls_count',
'FROM ({{=it._query}}) _cdb_formula'
].join('\n')),
'sum': dot.template([
'SELECT',
'sum({{=it._column}}*_feature_count) AS result,',
'(SELECT count(1) FROM ({{=it._query}}) _cdb_formula_nulls WHERE {{=it._column}} IS NULL) AS nulls_count',
'FROM ({{=it._query}}) _cdb_formula'
].join('\n')),
'avg': dot.template([
'SELECT',
'sum({{=it._column}}*_feature_count)/sum(_feature_count) AS result,',
'(SELECT count(1) FROM ({{=it._query}}) _cdb_formula_nulls WHERE {{=it._column}} IS NULL) AS nulls_count',
'FROM ({{=it._query}}) _cdb_formula'
].join('\n')),
};
function Formula(query, options, queryRewriter, queryRewriteData, params) {
BaseOverviewsDataview.call(this, query, options, BaseDataview, queryRewriter, queryRewriteData, params);
this.column = options.column || '1';
this.operation = options.operation;
}
Formula.prototype = Object.create(BaseOverviewsDataview.prototype);
Formula.prototype.constructor = Formula;
module.exports = Formula;
Formula.prototype.sql = function(psql, filters, override, callback) {
var formulaQueryTpl = formulaQueryTpls[this.operation];
if ( formulaQueryTpl ) {
// supported formula for use with overviews
var formulaSql = formulaQueryTpl({
_query: this.rewrittenQuery(this.query),
_operation: this.operation,
_column: this.column
});
callback = callback || override;
return callback(null, formulaSql);
}
// default behaviour
return this.defaultSql(psql, filters, override, callback);
};