cross join

Syntax

cj(leftTable, rightTable)

Arguments

leftTable and rightTable are the tables to be joined.

SQL-compatible cross join

select column_name(s)
from leftTable cross join rightTable

Details

Return the Cartesian product of two tables. If the left table has n rows and the right table has m rows, then the cross join function returns n*m rows.

Examples

a = table(2010 2011 2012 as year)
b = table(`IBM`C`AAPL as Ticker);
a;

year

2010

2011

2012

b;

Ticker

IBM

C

AAPL

cj(a,b);

year

Ticker

2010

IBM

2010

C

2010

AAPL

2011

IBM

2011

C

2011

AAPL

2012

IBM

2012

C

2012

AAPL

select * from cj(a,b) where year>2010;
// equivalent to `select * from a cross join b where year>2010`

year

Ticker

2011

IBM

2011

C

2011

AAPL

2012

IBM

2012

C

2012

AAPL

In contrast, join(<-) simply merges two tables’ columns

join(a,b);

year

Ticker

2010

IBM

2011

C

2012

AAPL