我在neo4j eclipse实现中遇到以下问题:
1。我收到限制功能的错误
Code:
String rows = "";
try ( Transaction ignored = graphDb.beginTx();
Result result = graphDb.execute( "match(pr:Provider)-[t:TREATS]->(p:Problem) return pr.prdes as Name, t.pprcount as Visits, limit 5" ) )
{
while ( result.hasNext() )
{
Map<String,Object> row = result.next();
for ( Entry<String,Object> column : row.entrySet() )
{
rows += column.getKey() + ": " + column.getValue() + "; ";
}
rows += "n";
}
}
System.out.println(""+rows);
}
Output:
Exception in thread "main" org.neo4j.graphdb.QueryExecutionException: Invalid input '5': expected whitespace, comment, node labels, MapLiteral, a parameter, a relationship pattern, '(', '.', '[', "=~", IN, IS, '^', '*', '/', '%', '+', '-', '<', '>', "<=", ">=", '=', "<>", "!=", AND, XOR, OR, AS, ',', ORDER, SKIP, LIMIT, LOAD CSV, START, MATCH, UNWIND, MERGE, CREATE, SET, DELETE, REMOVE, FOREACH, WITH, RETURN, UNION, ';' or end of input (line 1, column 97 (offset: 96)) "match(pr:Provider)-[t:TREATS]->(p:Problem) return pr.prdes as Name, t.pprcount as Visits, limit 5"
- 此外,在没有限制子句的情况下执行上述查询大约需要50分钟。那么如何提高性能速度呢
limits
之前不能有逗号,请尝试
match(pr:Provider)-[t:TREATS]->(p:Problem)
return pr.prdes as Name, t.pprcount as Visits limit 5
相反。
由于这是一个没有定义起点的全局查询,它的执行时间当然取决于您的数据大小。