projection

Documentation

Overview

Package projection implements the utilities for the projection query.

A projection query between sets (columnsA,filterA) and (columnsB,filterB) asserts whether the columnsA filtered by filterA is the same as columnsB filtered by filterB, preserving the order.

Example:

FilterA = (1,0,0,1,1), ColumnA := (aO,a1,a2,a3,a4)

FiletrB := (0,0,1,0,0,0,0,0,1,1), ColumnB :=(b0,b1,b2,b3,b4,b5,b6,b7,b8,b9)

Thus we have,

ColumnA filtered by FilterA = (a0,a3,a4)

ColumnB filtered by FilterB = (b2,b8,b9)

The projection query checks if a0 = b2, a3 = b8, a4 = b9

Note that the query imposes that:

• the number of 1 in the filters are equal
• the order of filtered elements is preserved

Index

• func InsertProjection(comp *wizard.CompiledIOP, queryName ifaces.QueryID, ...)

Functions

func InsertProjection

func InsertProjection(
	comp *wizard.CompiledIOP,
	queryName ifaces.QueryID,
	columnsA, columnsB []ifaces.Column,
	filterA, filterB ifaces.Column,
)

InsertProjection applies a projection query between sets (columnsA, filterA) and (columnsB,filterB).

Note: The filters are supposed to be binary. These binary constraints are not handled here and should have been imposed before calling the function.