/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
LOAD 'age';
SET search_path TO ag_catalog;
SELECT create_graph('cypher_merge');
NOTICE:  graph "cypher_merge" has been created
 create_graph 
--------------
 
(1 row)

/*
 * Section 1: MERGE with single vertex
 */
/*
 * test 1: Single MERGE Clause, path doesn't exist
 */
--test query
SELECT * FROM cypher('cypher_merge', $$MERGE (n {i: "Hello Merge"})$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                                        n                                         
----------------------------------------------------------------------------------
 {"id": 281474976710657, "label": "", "properties": {"i": "Hello Merge"}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 2: Single MERGE Clause, path exists
 */
--data setup
SELECT * FROM cypher('cypher_merge', $$CREATE ({i: "Hello Merge"}) $$) AS (a agtype);
 a 
---
(0 rows)

--test_query
SELECT * FROM cypher('cypher_merge', $$MERGE ({i: "Hello Merge"})$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                                        n                                         
----------------------------------------------------------------------------------
 {"id": 281474976710658, "label": "", "properties": {"i": "Hello Merge"}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 3: Prev clause returns no results, no data created
 */
--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE ({i: n.i})$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
 n 
---
(0 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 4: Prev clause has results, path exists
 */
--test query
SELECT * FROM cypher('cypher_merge', $$CREATE ({i: "Hello Merge"}) $$) AS (a agtype);
 a 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE ({i: n.i})$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                                        n                                         
----------------------------------------------------------------------------------
 {"id": 281474976710659, "label": "", "properties": {"i": "Hello Merge"}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 5: Prev clause has results, path does not exist (differnt property name)
 */
--data setup
SELECT * FROM cypher('cypher_merge', $$CREATE ({i: "Hello Merge"}) $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE ({j: n.i})$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                                        n                                         
----------------------------------------------------------------------------------
 {"id": 281474976710660, "label": "", "properties": {"i": "Hello Merge"}}::vertex
 {"id": 281474976710661, "label": "", "properties": {"j": "Hello Merge"}}::vertex
(2 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 6: MERGE with no prev clause, filters correctly, data created
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ({i: 2}) $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MERGE (n {i: 1}) RETURN n$$) AS (a agtype);
                                  a                                   
----------------------------------------------------------------------
 {"id": 281474976710663, "label": "", "properties": {"i": 1}}::vertex
(1 row)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                                  n                                   
----------------------------------------------------------------------
 {"id": 281474976710662, "label": "", "properties": {"i": 2}}::vertex
 {"id": 281474976710663, "label": "", "properties": {"i": 1}}::vertex
(2 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 7: MERGE with no prev clause, filters correctly, no data created
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ({i: 1}) $$) AS (a agtype);
 a 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$CREATE ({i: 1}) $$) AS (a agtype);
 a 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$CREATE ({i: 2}) $$) AS (a agtype);
 a 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$CREATE () $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MERGE (n {i: 1}) RETURN n$$) AS (a agtype);
                                  a                                   
----------------------------------------------------------------------
 {"id": 281474976710664, "label": "", "properties": {"i": 1}}::vertex
 {"id": 281474976710665, "label": "", "properties": {"i": 1}}::vertex
(2 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                                  n                                   
----------------------------------------------------------------------
 {"id": 281474976710664, "label": "", "properties": {"i": 1}}::vertex
 {"id": 281474976710665, "label": "", "properties": {"i": 1}}::vertex
 {"id": 281474976710666, "label": "", "properties": {"i": 2}}::vertex
 {"id": 281474976710667, "label": "", "properties": {}}::vertex
(4 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * Section 2: MERGE with edges
 */
/*
 * test 8: MERGE creates edge
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE () $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE (n)-[:e]->(:v)$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n)-[e:e]->(m:v) RETURN n, e, m$$) AS (n agtype, e agtype, m agtype);
                               n                                |                                                           e                                                            |                                m                                 
----------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------
 {"id": 281474976710668, "label": "", "properties": {}}::vertex | {"id": 844424930131969, "label": "e", "end_id": 1125899906842625, "start_id": 281474976710668, "properties": {}}::edge | {"id": 1125899906842625, "label": "v", "properties": {}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 9: edge already exists
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ()-[:e]->() $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MERGE (n)-[:e]->(:v)$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (n)-[e:e]->(m:v) RETURN n, e, m$$) AS (n agtype, e agtype, m agtype);
                               n                                |                                                           e                                                            |                                m                                 
----------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------
 {"id": 281474976710671, "label": "", "properties": {}}::vertex | {"id": 844424930131971, "label": "e", "end_id": 1125899906842626, "start_id": 281474976710671, "properties": {}}::edge | {"id": 1125899906842626, "label": "v", "properties": {}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 10: edge doesn't exist, using MATCH
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE () $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE (n)-[:e]->(:v)$$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (n)-[e:e]->(m:v) RETURN n, e, m$$) AS (n agtype, e agtype, m agtype);
                               n                                |                                                           e                                                            |                                m                                 
----------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------
 {"id": 281474976710672, "label": "", "properties": {}}::vertex | {"id": 844424930131972, "label": "e", "end_id": 1125899906842627, "start_id": 281474976710672, "properties": {}}::edge | {"id": 1125899906842627, "label": "v", "properties": {}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 11: edge already exists, using MATCH
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ()-[:e]->() $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE (n)-[:e]->(:v)$$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (n)-[e:e]->(m:v) RETURN n, e, m$$) AS (n agtype, e agtype, m agtype);
                               n                                |                                                           e                                                            |                                m                                 
----------------------------------------------------------------+------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------
 {"id": 281474976710673, "label": "", "properties": {}}::vertex | {"id": 844424930131974, "label": "e", "end_id": 1125899906842628, "start_id": 281474976710673, "properties": {}}::edge | {"id": 1125899906842628, "label": "v", "properties": {}}::vertex
 {"id": 281474976710674, "label": "", "properties": {}}::vertex | {"id": 844424930131975, "label": "e", "end_id": 1125899906842629, "start_id": 281474976710674, "properties": {}}::edge | {"id": 1125899906842629, "label": "v", "properties": {}}::vertex
(2 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 12: Partial Path Exists, creates whole path
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ()-[:e]->() $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MERGE ()-[:e]->()-[:e]->()$$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
--Returns 3. One for the data setup and 2 for the longer path in MERGE
SELECT count(*) FROM cypher('cypher_merge', $$MATCH p=()-[e:e]->() RETURN p$$) AS (p agtype)
-- Returns 1, the path created in MERGE
SELECT count(*) FROM cypher('cypher_merge', $$MATCH p=()-[:e]->()-[]->() RETURN p$$) AS (p agtype);
ERROR:  syntax error at or near "SELECT"
LINE 3: SELECT count(*) FROM cypher('cypher_merge', $$MATCH p=()-[:e...
        ^
-- 5 vertices total should have been created
SELECT count(*) FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
 count 
-------
     5
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 13: edge doesn't exists (differnt label), using MATCH
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ()-[:e]->() $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) MERGE (n)-[:e_new]->(:v)$$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (n)-[e]->(m:v) RETURN n, e, m$$) AS (n agtype, e agtype, m agtype);
                               n                                |                                                              e                                                              |                                m                                 
----------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------
 {"id": 281474976710680, "label": "", "properties": {}}::vertex | {"id": 1407374883553281, "label": "e_new", "end_id": 1125899906842630, "start_id": 281474976710680, "properties": {}}::edge | {"id": 1125899906842630, "label": "v", "properties": {}}::vertex
 {"id": 281474976710681, "label": "", "properties": {}}::vertex | {"id": 1407374883553282, "label": "e_new", "end_id": 1125899906842631, "start_id": 281474976710681, "properties": {}}::edge | {"id": 1125899906842631, "label": "v", "properties": {}}::vertex
(2 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 14: edge doesn't exists (different label), without MATCH
 */
-- setup
SELECT * FROM cypher('cypher_merge', $$CREATE ()-[:e]->() $$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MERGE (n)-[:e_new]->(:v)$$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (n)-[e]->(m:v) RETURN n, e, m$$) AS (n agtype, e agtype, m agtype);
                               n                                |                                                              e                                                              |                                m                                 
----------------------------------------------------------------+-----------------------------------------------------------------------------------------------------------------------------+------------------------------------------------------------------
 {"id": 281474976710684, "label": "", "properties": {}}::vertex | {"id": 1407374883553283, "label": "e_new", "end_id": 1125899906842632, "start_id": 281474976710684, "properties": {}}::edge | {"id": 1125899906842632, "label": "v", "properties": {}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * Section 3: MERGE with writing clauses
 */
/*
 * test 15:
 */
--test query
SELECT * FROM cypher('cypher_merge', $$CREATE () MERGE (n)$$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (n agtype);
                               n                                
----------------------------------------------------------------
 {"id": 281474976710685, "label": "", "properties": {}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 16:
 */
--test query
SELECT * FROM cypher('cypher_merge', $$CREATE (n) WITH n as a MERGE (a)-[:e]->() $$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH p=()-[:e]->() RETURN p$$) AS (p agtype);
                                                                                                                               p                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710687, "label": "", "properties": {}}::vertex, {"id": 844424930131981, "label": "e", "end_id": 281474976710688, "start_id": 281474976710687, "properties": {}}::edge, {"id": 281474976710688, "label": "", "properties": {}}::vertex]::path
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 17:
 * XXX: Incorrect Output. To FIX
 */
--test query
SELECT * FROM cypher('cypher_merge', $$CREATE (n) MERGE (n)-[:e]->() $$) AS (a agtype);
ERROR:  end_id() argument must resolve to a scalar value
--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH p=()-[:e]->() RETURN p$$) AS (p agtype);
 p 
---
(0 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 18:
 */
--test query
SELECT * FROM cypher('cypher_merge', $$CREATE (n {i : 1}) SET n.i = 2 MERGE ({i: 2}) $$) AS (a agtype);
ERROR:  missing FROM-clause entry for table "_age_default_alias_0"
LINE 5: SELECT * FROM cypher('cypher_merge', $$CREATE (n {i : 1}) SE...
                                               ^
--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (a) RETURN a$$) AS (a agtype);
 a 
---
(0 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 19:
 */
--test query
SELECT * FROM cypher('cypher_merge', $$CREATE (n {i : 1}) SET n.i = 2 WITH n as a MERGE ({i: 2}) $$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (a) RETURN a$$) AS (a agtype);
                                  a                                   
----------------------------------------------------------------------
 {"id": 281474976710690, "label": "", "properties": {"i": 2}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 20:
 */
--data setup
SELECT * FROM cypher('cypher_merge', $$CREATE (n {i : 1})$$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n {i : 1}) SET n.i = 2 WITH n as a MERGE ({i: 2}) $$) AS (a agtype);
 a 
---
(0 rows)

--validate created correctly
SELECT * FROM cypher('cypher_merge', $$MATCH (a) RETURN a$$) AS (a agtype);
                                  a                                   
----------------------------------------------------------------------
 {"id": 281474976710691, "label": "", "properties": {"i": 2}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 21:
 */
--data setup
SELECT * FROM cypher('cypher_merge', $$CREATE (n {i : 1})$$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n {i : 1}) DELETE n  MERGE (n)-[:e]->() $$) AS (a agtype);
ERROR:  vertex assigned to variable n was deleted
--validate, transaction was rolled back because of the error message
SELECT * FROM cypher('cypher_merge', $$MATCH (a) RETURN a$$) AS (a agtype);
                                  a                                   
----------------------------------------------------------------------
 {"id": 281474976710692, "label": "", "properties": {"i": 1}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 22:
 * MERGE after MERGE
 */
SELECT * FROM cypher('cypher_merge', $$
    CREATE (n:Person {name : "Rob Reiner", bornIn: "New York"})
$$) AS (a agtype);
 a 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$
    CREATE (n:Person {name : "Michael Douglas", bornIn: "New Jersey"})
$$) AS (a agtype);
 a 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$
    CREATE (n:Person {name : "Martin Sheen", bornIn: "Ohio"})
$$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$
    MATCH (person:Person)
    MERGE (city:City {name: person.bornIn})
    MERGE (person)-[r:BORN_IN]->(city)
    RETURN person.name, person.bornIn, city
$$) AS (name agtype, bornIn agtype, city agtype);
       name        |    bornin    |                                          city                                           
-------------------+--------------+-----------------------------------------------------------------------------------------
 "Rob Reiner"      | "New York"   | {"id": 1970324836974593, "label": "City", "properties": {"name": "New York"}}::vertex
 "Martin Sheen"    | "Ohio"       | {"id": 1970324836974595, "label": "City", "properties": {"name": "Ohio"}}::vertex
 "Michael Douglas" | "New Jersey" | {"id": 1970324836974594, "label": "City", "properties": {"name": "New Jersey"}}::vertex
(3 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (a) RETURN a$$) AS (a agtype);
                                                           a                                                            
------------------------------------------------------------------------------------------------------------------------
 {"id": 1688849860263937, "label": "Person", "properties": {"name": "Rob Reiner", "bornIn": "New York"}}::vertex
 {"id": 1688849860263938, "label": "Person", "properties": {"name": "Michael Douglas", "bornIn": "New Jersey"}}::vertex
 {"id": 1688849860263939, "label": "Person", "properties": {"name": "Martin Sheen", "bornIn": "Ohio"}}::vertex
 {"id": 1970324836974593, "label": "City", "properties": {"name": "New York"}}::vertex
 {"id": 1970324836974594, "label": "City", "properties": {"name": "New Jersey"}}::vertex
 {"id": 1970324836974595, "label": "City", "properties": {"name": "Ohio"}}::vertex
(6 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 23:
 */
SELECT * FROM cypher('cypher_merge', $$MERGE ()-[:e]-()$$) AS (a agtype);
 a 
---
(0 rows)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH p=()-[]->() RETURN p$$) AS (a agtype);
                                                                                                                               a                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710693, "label": "", "properties": {}}::vertex, {"id": 844424930131982, "label": "e", "end_id": 281474976710694, "start_id": 281474976710693, "properties": {}}::edge, {"id": 281474976710694, "label": "", "properties": {}}::vertex]::path
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 24:
 */
SELECT * FROM cypher('cypher_merge', $$MERGE (a) RETURN a$$) AS (a agtype);
                               a                                
----------------------------------------------------------------
 {"id": 281474976710695, "label": "", "properties": {}}::vertex
(1 row)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH (a) RETURN a$$) AS (a agtype);
                               a                                
----------------------------------------------------------------
 {"id": 281474976710695, "label": "", "properties": {}}::vertex
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 25:
 */
SELECT * FROM cypher('cypher_merge', $$MERGE p=()-[:e]-() RETURN p$$) AS (a agtype);
                                                                                                                               a                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710696, "label": "", "properties": {}}::vertex, {"id": 844424930131983, "label": "e", "end_id": 281474976710697, "start_id": 281474976710696, "properties": {}}::edge, {"id": 281474976710697, "label": "", "properties": {}}::vertex]::path
(1 row)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH p=()-[]->() RETURN p$$) AS (a agtype);
                                                                                                                               a                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710696, "label": "", "properties": {}}::vertex, {"id": 844424930131983, "label": "e", "end_id": 281474976710697, "start_id": 281474976710696, "properties": {}}::edge, {"id": 281474976710697, "label": "", "properties": {}}::vertex]::path
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 26:
 */
SELECT * FROM cypher('cypher_merge', $$MERGE (a)-[:e]-(b) RETURN a$$) AS (a agtype);
                               a                                
----------------------------------------------------------------
 {"id": 281474976710698, "label": "", "properties": {}}::vertex
(1 row)

--validate
SELECT * FROM cypher('cypher_merge', $$MATCH p=()-[]->() RETURN p$$) AS (a agtype);
                                                                                                                               a                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710698, "label": "", "properties": {}}::vertex, {"id": 844424930131984, "label": "e", "end_id": 281474976710699, "start_id": 281474976710698, "properties": {}}::edge, {"id": 281474976710699, "label": "", "properties": {}}::vertex]::path
(1 row)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * test 27:
 */
SELECT  * FROM cypher('cypher_merge', $$CREATE p=()-[:e]->() RETURN p$$) AS (a agtype);
                                                                                                                               a                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710700, "label": "", "properties": {}}::vertex, {"id": 844424930131985, "label": "e", "end_id": 281474976710701, "start_id": 281474976710700, "properties": {}}::edge, {"id": 281474976710701, "label": "", "properties": {}}::vertex]::path
(1 row)

SELECT * FROM cypher('cypher_merge', $$MERGE p=()-[:e]-() RETURN p$$) AS (a agtype);
                                                                                                                               a                                                                                                                               
---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
 [{"id": 281474976710700, "label": "", "properties": {}}::vertex, {"id": 844424930131985, "label": "e", "end_id": 281474976710701, "start_id": 281474976710700, "properties": {}}::edge, {"id": 281474976710701, "label": "", "properties": {}}::vertex]::path
 [{"id": 281474976710701, "label": "", "properties": {}}::vertex, {"id": 844424930131985, "label": "e", "end_id": 281474976710701, "start_id": 281474976710700, "properties": {}}::edge, {"id": 281474976710700, "label": "", "properties": {}}::vertex]::path
(2 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * Section 4: Error Messages
 */
/*
 * test 28:
 * Only single paths allowed
 */
SELECT * FROM cypher('cypher_merge', $$MERGE (n), (m) RETURN n, m$$) AS (a agtype, b agtype);
ERROR:  syntax error at or near ","
LINE 8: SELECT * FROM cypher('cypher_merge', $$MERGE (n), (m) RETURN...
                                                        ^
/*
 * test 29:
 * Edges cannot reference existing variables
 */
SELECT * FROM cypher('cypher_merge', $$MATCH ()-[e]-() MERGE ()-[e]->()$$) AS (a agtype);
ERROR:  variable e already exists
LINE 5: ...cypher('cypher_merge', $$MATCH ()-[e]-() MERGE ()-[e]->()$$)...
                                                             ^
/*
 * test 30:
 * NULL vertex given to MERGE
 */
--data setup
SELECT * FROM cypher('cypher_merge', $$CREATE (n)$$) AS (a agtype);
 a 
---
(0 rows)

--test query
SELECT * FROM cypher('cypher_merge', $$MATCH (n) OPTIONAL MATCH (n)-[:e]->(m) MERGE (m)$$) AS (a agtype);
ERROR:  Existing variable m cannot be NULL in MERGE clause
-- validate only 1 vertex exits
SELECT * FROM cypher('cypher_merge', $$MATCH (n) RETURN n$$) AS (a agtype);
                               a                                
----------------------------------------------------------------
 {"id": 281474976710702, "label": "", "properties": {}}::vertex
(1 row)

--
-- MERGE/SET test
-- Node does exist, then set (github issue #235)
SELECT * FROM cypher('cypher_merge', $$ CREATE (n:node {name: 'Jason'}) RETURN n $$) AS (n agtype);
                                         n                                          
------------------------------------------------------------------------------------
 {"id": 2533274790395905, "label": "node", "properties": {"name": "Jason"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) RETURN n $$) AS (n agtype);
                                         n                                          
------------------------------------------------------------------------------------
 {"id": 2533274790395905, "label": "node", "properties": {"name": "Jason"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MERGE (n:node {name: 'Jason'}) SET n.name = 'Lisa' RETURN n $$) AS (n agtype);
                                         n                                         
-----------------------------------------------------------------------------------
 {"id": 2533274790395905, "label": "node", "properties": {"name": "Lisa"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) RETURN n $$) AS (n agtype);
                                         n                                         
-----------------------------------------------------------------------------------
 {"id": 2533274790395905, "label": "node", "properties": {"name": "Lisa"}}::vertex
(1 row)

-- Node doesn't exist, is created, then set
SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) DELETE n $$) AS (n agtype);
 n 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) RETURN n $$) AS (n agtype);
 n 
---
(0 rows)

SELECT * FROM cypher('cypher_merge', $$ MERGE (n:node {name: 'Jason'}) SET n.name = 'Lisa' RETURN n $$) AS (n agtype);
                                         n                                         
-----------------------------------------------------------------------------------
 {"id": 2533274790395906, "label": "node", "properties": {"name": "Lisa"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) RETURN n $$) AS (n agtype);
                                         n                                         
-----------------------------------------------------------------------------------
 {"id": 2533274790395906, "label": "node", "properties": {"name": "Lisa"}}::vertex
(1 row)

-- Multiple SETs
SELECT * FROM cypher('cypher_merge', $$ MERGE (n:node {name: 'Lisa'}) SET n.age = 23, n.gender = "Female" RETURN n $$) AS (n agtype);
                                                        n                                                         
------------------------------------------------------------------------------------------------------------------
 {"id": 2533274790395906, "label": "node", "properties": {"age": 23, "name": "Lisa", "gender": "Female"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) RETURN n $$) AS (n agtype);
                                                        n                                                         
------------------------------------------------------------------------------------------------------------------
 {"id": 2533274790395906, "label": "node", "properties": {"age": 23, "name": "Lisa", "gender": "Female"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MERGE (n:node {name: 'Jason'}) SET n.name = 'Lisa', n.age = 23, n.gender = 'Female' RETURN n $$) AS (n agtype);
                                                        n                                                         
------------------------------------------------------------------------------------------------------------------
 {"id": 2533274790395907, "label": "node", "properties": {"age": 23, "name": "Lisa", "gender": "Female"}}::vertex
(1 row)

SELECT * FROM cypher('cypher_merge', $$ MATCH (n:node) RETURN n $$) AS (n agtype);
                                                        n                                                         
------------------------------------------------------------------------------------------------------------------
 {"id": 2533274790395906, "label": "node", "properties": {"age": 23, "name": "Lisa", "gender": "Female"}}::vertex
 {"id": 2533274790395907, "label": "node", "properties": {"age": 23, "name": "Lisa", "gender": "Female"}}::vertex
(2 rows)

--clean up
SELECT * FROM cypher('cypher_merge', $$MATCH (n) DETACH DELETE n $$) AS (a agtype);
 a 
---
(0 rows)

/*
 * Clean up graph
 */
SELECT drop_graph('cypher_merge', true);
NOTICE:  drop cascades to 9 other objects
DETAIL:  drop cascades to table cypher_merge._ag_label_vertex
drop cascades to table cypher_merge._ag_label_edge
drop cascades to table cypher_merge.e
drop cascades to table cypher_merge.v
drop cascades to table cypher_merge.e_new
drop cascades to table cypher_merge."Person"
drop cascades to table cypher_merge."City"
drop cascades to table cypher_merge."BORN_IN"
drop cascades to table cypher_merge.node
NOTICE:  graph "cypher_merge" has been dropped
 drop_graph 
------------
 
(1 row)