PREVIEW EDGE

Commands › Edges · Admins only, through sercha_define or a tenant file

Resolves an edge's rule over both sides and reports the pair count, how many rows on each side link, the count per rule and up to ten sample pairs. Nothing is written.

Syntax

PREVIEW EDGE <name>
PREVIEW EDGE <name> ON <relation> [ WHERE ... ] <VERB> <relation> [ WHERE ... ]
  LINK BY <rule> [, ...] [ RESOLVE { EXACT | FUZZY } ]

Parameters

Parameter	Description
<name>	With no body, the stored edge of that name is previewed. With a body, the name only labels the result.
ON ... LINK BY ...	An edge body, written exactly as in CREATE EDGE.

Usage notes

• The result has three columns, what, count and detail. Its rows are pairs, one row per side (<relation> rows, with linked and unmatched counts), one rule: ... row per rule, and sample rows showing left_key -> right_key (rule): evidence.
• An edge written out in the statement reads entity and view sides as you, as it would once you declare it.
• Without a body, a name with no stored edge is an error that asks for the body.

Examples

PREVIEW EDGE order_customer
  ON data.orders PLACED_BY data.customers
  LINK BY customer_no = account_no;

what	count	detail
pairs	1482
data.orders rows	1530	1482 linked, 48 unmatched
data.customers rows	312	297 linked, 15 unmatched
rule: customer_no = account_no	1482
sample	1	o-10021 -> c-0042 (customer_no = account_no): customer_no = c-0042

Preview a stored edge:

PREVIEW EDGE order_customer

See also

CREATE EDGE · REFRESH EDGES · DROP EDGE