Ensure edge records are output as RELATE statements in SQL export

Closes #1496

lib/src/doc/edges.rs

@@ -5,8 +5,10 @@ use crate::dbs::Transaction;
 use crate::dbs::Workable;
 use crate::doc::Document;
 use crate::err::Error;
+use crate::sql::paths::EDGE;
 use crate::sql::paths::IN;
 use crate::sql::paths::OUT;
+use crate::sql::value::Value;
 use crate::sql::Dir;
 
 impl<'a> Document<'a> {
@@ -44,6 +46,7 @@ impl<'a> Document<'a> {
 			let key = crate::key::graph::new(opt.ns(), opt.db(), &r.tb, &r.id, i, rid);
 			run.set(key, vec![]).await?;
 			// Store the edges on the record
+			self.current.to_mut().set(ctx, opt, txn, &*EDGE, Value::True).await?;
 			self.current.to_mut().set(ctx, opt, txn, &*IN, l.clone().into()).await?;
 			self.current.to_mut().set(ctx, opt, txn, &*OUT, r.clone().into()).await?;
 		}

lib/src/doc/purge.rs

@@ -6,6 +6,7 @@ use crate::doc::Document;
 use crate::err::Error;
 use crate::sql::dir::Dir;
 use crate::sql::edges::Edges;
+use crate::sql::paths::EDGE;
 use crate::sql::paths::IN;
 use crate::sql::paths::OUT;
 use crate::sql::statements::DeleteStatement;
@@ -38,8 +39,8 @@ impl<'a> Document<'a> {
 		let key = crate::key::thing::new(opt.ns(), opt.db(), &rid.tb, &rid.id);
 		run.del(key).await?;
 		// Purge the record edges
-		match (self.initial.pick(&*IN), self.initial.pick(&*OUT)) {
-			(Value::Thing(ref l), Value::Thing(ref r)) => {
+		match (self.initial.pick(&*EDGE), self.initial.pick(&*IN), self.initial.pick(&*OUT)) {
+			(Value::True, Value::Thing(ref l), Value::Thing(ref r)) => {
 				// Get temporary edge references
 				let (ref o, ref i) = (Dir::Out, Dir::In);
 				// Purge the left pointer edge

lib/src/kvs/tx.rs

@@ -7,7 +7,11 @@ use crate::key::thing;
 use crate::kvs::cache::Cache;
 use crate::kvs::cache::Entry;
 use crate::sql;
+use crate::sql::paths::EDGE;
+use crate::sql::paths::IN;
+use crate::sql::paths::OUT;
 use crate::sql::thing::Thing;
+use crate::sql::Value;
 use channel::Sender;
 use sql::permission::Permissions;
 use sql::statements::DefineDatabaseStatement;
@@ -1461,12 +1465,26 @@ impl Transaction {
 								if n == i + 1 {
 									nxt = Some(k.clone());
 								}
-								// Parse the key-value
+								// Parse the key and the value
 								let k: crate::key::thing::Thing = (&k).into();
 								let v: crate::sql::value::Value = (&v).into();
 								let t = Thing::from((k.tb, k.id));
-								// Write record
-								chn.send(bytes!(format!("UPDATE {} CONTENT {};", t, v))).await?;
+								// Check if this is a graph edge
+								match (v.pick(&*EDGE), v.pick(&*IN), v.pick(&*OUT)) {
+									// This is a graph edge record
+									(Value::True, Value::Thing(l), Value::Thing(r)) => {
+										let sql = format!(
+											"RELATE {} -> {} -> {} CONTENT {};",
+											l, t, r, v
+										);
+										chn.send(bytes!(sql)).await?;
+									}
+									// This is a normal record
+									_ => {
+										let sql = format!("UPDATE {} CONTENT {};", t, v);
+										chn.send(bytes!(sql)).await?;
+									}
+								}
 							}
 							continue;
 						}

lib/src/sql/paths.rs

@@ -22,3 +22,5 @@ pub static IN: Lazy<[Part; 1]> = Lazy::new(|| [Part::from("in")]);
 pub static OUT: Lazy<[Part; 1]> = Lazy::new(|| [Part::from("out")]);
 
 pub static META: Lazy<[Part; 1]> = Lazy::new(|| [Part::from("__")]);
+
+pub static EDGE: Lazy<[Part; 1]> = Lazy::new(|| [Part::from("__")]);