MarkLogic 12 EA 2 Product Documentation

ModifyPlan.prototype.existsJoin

ModifyPlan.prototype.existsJoin(
   rightPlan as String,
   [ondef as String],
   [condition as xs.boolean]
) as ModifyPlan

Summary

This method is a filtering join that filters based on whether the join exists or not but doesn't add any columns.

It filters the left row set to the rows that have a join in the right row set.

Usage Notes

existsJoin is a method of the following classes:

• AccessPlan
• ModifyPlan

The library functions for building the existsJoin parameters are as follows:

• op.on

Example

// It filters out {'r1':1, 'k1':'a'} in p1 as value 'a' exists in column 'k2' of p2
const op = require('/MarkLogic/optic');

const p1 = op.fromLiterals([
    {'r1':1, 'k1':'a'},
    {'r1':2, 'k1':'b'}
  ]);
const p2 = op.fromLiterals([
    {'r2':3, 'k2':'a'},
    {'r2':4, 'k2':'c'}
  ]);
p1.existsJoin(p2, op.on('k1', 'k2')).result();