from py2neo import Graph, Node, Relationship, Subgraph

# 修正版本查询代码
#version = db.run("CALL dbms.components() YIELD versions UNWIND versions AS version RETURN version").evaluate()
#print(f"Neo4j 版本: {version}")

def clear(db):
    # 清空数据
    db.run("MATCH (n) DETACH DELETE n")

    # 分步删除约束和索引
    try:
        # 删除约束
        constraints = db.run("SHOW CONSTRAINTS YIELD name").data()
        for constr in constraints:
            db.run(f"DROP CONSTRAINT `{constr['name']}`")

        # 删除索引
        indexes = db.run("SHOW INDEXES YIELD name, type WHERE type <> 'LOOKUP'").data()
        for idx in indexes:
            db.run(f"DROP INDEX `{idx['name']}`")
    except Exception as e:
        print(f"删除操作失败: {e}")