py2neo 查询语句
NodeMatcher
>>> from py2neo import Graph
>>> from py2neo.matching import *
>>> g = Graph()
>>> nodes = NodeMatcher(g)
>>> keanu = nodes.match("Person", name="Keanu Reeves").first()
>>> keanu
Node('Person', born=1964, name='Keanu Reeves')
可以对查询结果进行进一步查询：文章来源：https://www.toymoban.com/news/detail-712685.html
按ID查找节点
>>> matches.get(1234)
Node('Person', name='Alice')
对查找结果排序
match.order_by("_.name", "max(_.a, _.b)")
根据where语句查询
>>> nodes.match("Person").where("_.born % 10 = 0").all()
[Node('Person', born=1950, name='Ed Harris'),
Node('Person', born=1960, name='Hugo Weaving'),
Node('Person', born=1940, name='Al Pacino'),
Node('Person', born=1970, name='Jay Mohr'),
Node('Person', born=1970, name='River Phoenix'),
Node('Person', born=1940, name='James L. Brooks'),
Node('Person', born=1960, name='Annabella Sciorra'),
Node('Person', born=1970, name='Ethan Hawke'),
Node('Person', born=1940, name='James Cromwell'),
Node('Person', born=1950, name='John Patrick Stanley'),
Node('Person', born=1970, name='Brooke Langton'),
Node('Person', born=1930, name='Gene Hackman'),
Node('Person', born=1950, name='Howard Deutch'),
Node('Person', born=1930, name='Richard Harris'),
Node('Person', born=1930, name='Clint Eastwood'),
Node('Person', born=1940, name='John Hurt'),
Node('Person', born=1960, name='John Goodman'),
Node('Person', born=1980, name='Christina Ricci'),
Node('Person', born=1960, name='Oliver Platt')]
match.where("_.name =~ 'J.*'")
=~是不等于的意思，.是任意字符，*是前面的字符大于等于0个。整体意思就是查到节点中name属性不以J开头的节点文章来源地址https://www.toymoban.com/news/detail-712685.html
判断是否为空
IS_NULL()
查询以…开头的节点
>>> nodes.match("Person", name=STARTS_WITH("Kevin")).all()
[Node('Person', born=1958, name='Kevin Bacon'),
Node('Person', born=1957, name='Kevin Pollak')]
查询以…结尾的节点
>>> nodes.match("Person", name=ENDS_WITH("Wachowski")).all()
[Node('Person', born=1967, name='Andy Wachowski'),
Node('Person', born=1965, name='Lana Wachowski')]
查询包含某个字符串的节点
>>> nodes.match("Person", name=CONTAINS("eve")).all()
[Node('Person', born=1967, name='Steve Zahn'),
Node('Person', born=1964, name='Keanu Reeves')]
按正则表达式查找
>>> nodes.match("Person", name=LIKE("Ke.*n")).all()
[Node('Person', born=1958, name='Kevin Bacon'),
Node('Person', born=1962, name='Kelly Preston')]
包含在列表当中
>>> nodes.match("Person", born=IN([1962, 1964, 1966])).all()
[Node('Person', born=1964, name='Keanu Reeves'),
Node('Person', born=1962, name='Tom Cruise'),
Node('Person', born=1962, name='Demi Moore'),
Node('Person', born=1966, name='Kiefer Sutherland'),
Node('Person', born=1962, name='Anthony Edwards'),
Node('Person', born=1962, name='Kelly Preston'),
Node('Person', born=1966, name='John Cusack'),
Node('Person', born=1962, name="Rosie O'Donnell"),
Node('Person', born=1966, name='Halle Berry'),
Node('Person', born=1966, name='Matthew Fox')]
与查找
>>> nodes.match("Person", born=AND(GE(1964), LE(1966))).all()
[Node('Person', born=1965, name='John C. Reilly'),
Node('Person', born=1964, name='Keanu Reeves'),
Node('Person', born=1965, name='Lana Wachowski'),
Node('Person', born=1966, name='Kiefer Sutherland'),
Node('Person', born=1966, name='John Cusack'),
Node('Person', born=1966, name='Halle Berry'),
Node('Person', born=1965, name='Tom Tykwer'),
Node('Person', born=1966, name='Matthew Fox')]
或查找
>>> nodes.match("Person", name=OR(STARTS_WITH("H"), ENDS_WITH("h"))).all()
[Node('Person', born=1960, name='Hugo Weaving'),
Node('Person', born=1943, name='J.T. Walsh'),
Node('Person', born=1941, name='Jim Cash'),
Node('Person', born=1963, name='Helen Hunt'),
Node('Person', born=1950, name='Howard Deutch'),
Node('Person', born=1966, name='Halle Berry'),
Node('Person', born=1985, name='Emile Hirsch')]
异或查找
>>> nodes.match("Person", name=XOR(STARTS_WITH("H"), ENDS_WITH("h"))).all()
[Node('Person', born=1960, name='Hugo Weaving'),
Node('Person', born=1943, name='J.T. Walsh'),
Node('Person', born=1941, name='Jim Cash'),
Node('Person', born=1963, name='Helen Hunt'),
Node('Person', born=1966, name='Halle Berry'),
Node('Person', born=1985, name='Emile Hirsch')]
限制查找的数量
>>> nodes.match("Person").where(name=LIKE("K.*")).order_by("_.name").limit(3).all()
[Node('Person', born=1964, name='Keanu Reeves'),
Node('Person', born=1957, name='Kelly McGillis'),
Node('Person', born=1962, name='Kelly Preston')]
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