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neo4j批量导入neo4j-import

itxm 2021年06月14日 数据库 349 0


neo4j数据批量导入

目前主要有以下几种数据插入方式:(转自:如何将大规模数据导入Neo4j
Cypher CREATE 语句,为每一条数据写一个CREATE
Cypher LOAD CSV 语句,将数据转成CSV格式,通过LOAD CSV读取数据。
官方提供的Java API —— Batch Inserter
大牛编写的 Batch Import 工具
官方提供的 neo4j-import 工具

这里写图片描述

这边重点来说一下官方最快的neo4j-import,使用的前提条件:

  • graph.db需要清空;
  • neo4j需要停掉;
  • 接受CSV导入,而且格式较为固定;
  • 试用场景:首次导入
  • 节点名字需要唯一

比较适用:

首次导入,无法迭代更新
   
    

来看一下官方案例:Use the Import tool


1 neo4j基本参数

1.1 启动与关闭:

bin\neo4j start 
bin\neo4j stop 
bin\neo4j restart 
bin\neo4j status
   
    

1.2 neo4j-admin的参数:控制内存

来源:10.5. Memory recommendations
这里写图片描述

1.2.1 memrec 是查看参考内存设置

neo4j-admin memrec [--memory=<memory dedicated to Neo4j>] [--database=<name>]
   
    
Option Default Description
–memory The memory capacity of the machine The amount of memory to allocate to Neo4j. Valid units are: k, K, m, M, g, G.
–database graph.db The name of the database. This option will generate numbers for Lucene indexes, and for data volume and native indexes in the database. These can be used as an input into more detailed memory analysis.

参考:

$neo4j-home> bin/neo4j-admin memrec --memory=16g
   
    
  • 1

1.2.2 指定缓存–pagecache

还有--pagecache单条命令指定缓存:

bin/neo4j-admin backup --from=192.168.1.34 --backup-dir=/mnt/backup --name=graph.db-backup --pagecache=4G
   
    
  • 1

指的是,再该条导入数据的指令下,缓存设置。

1.3 neo4j-admin的参数:Dump and load databases - 线下备份

执行该两步操作,需要关闭数据库。参考:10.7. Dump and load databases

dump过程:把graph.db转存到.dump

需要关闭数据库

$neo4j-home> bin/neo4j-admin dump --database=graph.db --to=/backups/graph.db/2016-10-02.dump 
$neo4j-home> ls /backups/graph.db 
$neo4j-home> 2016-10-02.dump
   
    

load过程:把.dumpload进来

好像可以不用关闭

$neo4j-home> bin/neo4j stop 
Stopping Neo4j.. stopped 
$neo4j-home> bin/neo4j-admin load --from=/backups/graph.db/2016-10-02.dump --database=graph.db --force
   
    

如果带--force,那么load之后,会更新所有的存在着的.db(any existing database gets overwritten.

1.4 neo4j-admin的参数:backup and restore - 在线备份

参考:6.2. Perform a backup

在线备份backup :

$neo4j-home> export HEAP_SIZE=2G 
$neo4j-home> mkdir /mnt/backup 
$neo4j-home> bin/neo4j-admin backup --from=192.168.1.34 --backup-dir=/mnt/backup --name=graph.db-backup --pagecache=4G
   
    

backup 进临时文件夹之中。

追加备份:

$neo4j-home> export HEAP_SIZE=2G 
$neo4j-home> bin/neo4j-admin backup --from=192.168.1.34 --backup-dir=/mnt/backup --name=graph.db-backup --fallback-to-full=true --check-consistency=true --pagecache=4G
   
    

.


2 简单demo

movies.csv.

movieId:ID,title,year:int,:LABEL 
tt0133093,"The Matrix",1999,Movie 
tt0234215,"The Matrix Reloaded",2003,Movie;Sequel 
tt0242653,"The Matrix Revolutions",2003,Movie;Sequel
   
    

其中,title是属性,注意此时需要有双引号;year:int也是属性,只不过该属性是数值型的;
:LABEL:ID一样生成了一个新节点,也就是一套数据可以通过:生成双节点
actors.csv.

personId:ID,name,:LABEL 
keanu,"Keanu Reeves",Actor 
laurence,"Laurence Fishburne",Actor 
carrieanne,"Carrie-Anne Moss",Actor
   
    

roles.csv.
其中,:LABEL非常有意思,是节点的附属属性,其中personId:ID一定是唯一的:LABEL可以不唯一。
而且,载入之后,:LABEL单独会成为新的节点,而且是去重的。

:START_ID,role,:END_ID,:TYPE 
keanu,"Neo",tt0133093,ACTED_IN 
keanu,"Neo",tt0234215,ACTED_IN 
keanu,"Neo",tt0242653,ACTED_IN 
laurence,"Morpheus",tt0133093,ACTED_IN 
laurence,"Morpheus",tt0234215,ACTED_IN 
laurence,"Morpheus",tt0242653,ACTED_IN 
carrieanne,"Trinity",tt0133093,ACTED_IN 
carrieanne,"Trinity",tt0234215,ACTED_IN 
carrieanne,"Trinity",tt0242653,ACTED_IN
   
    

其中,这个节点的属性,role没有标注:,role是属性,可以加双引号,也可以不加。最好是指定一下格式,譬如:int为数值型,还有字符型roles:string[]

linux执行:

neo4j_home$ bin/neo4j-admin import --nodes import/movies.csv --nodes import/actors.csv --relationships import/roles.csv
   
    

其中,之前老版本批量导入是:neo4j-import,现在批量导入是:neo4j-admin

window执行:

neo4j-import.bat --into ../data/databases/graph.db --id-type string --nodes:attribute ../import/node_attribute.csv --relationships ../import/product_SecondLeaf.csv --relationships ../import/scene_isDemond.csv
   
    
  • --into,是指定存入名字,在不同的尝试,可以修改名字。
  • --nodes:attribute,其中,nodes:后面是用来指定节点大类的名称的
  • --id-type string,,The –id-type string is indicating that all :ID columns contain alphanumeric values (there is an optimization for numeric-only id’s).之前节点ID只能由数字组成,现在允许字符+数字共同定义。

linux最后启动:

./bin/neo4j start
   
    

window 最后启动:

neo4j.bat console
   
    

执行时候错误信息解析:

1 报错信息留存在bad.log

\data\databases\graph.db\bad.log
   
    

global id space的报错为节点未定义,或者节点重复

2 如果节点不唯一,直接报错:
global id space,同时后续的内容中端上传,需要删除data/database /graph.db,重新操作一遍


3 其他导入情况列举

主要来源于:B.2. Use the Import tool

3.1 不同分隔符导入

如果导入的节点信息为:

:START_ID;role;:END_ID;:TYPE 
keanu;'Neo';tt0133093;ACTED_IN 
keanu;'Neo';tt0234215;ACTED_IN
   
    

那么可以通过--delimiter来进行指定。

neo4j_home$ bin/neo4j-admin import --nodes import/movies2.csv --nodes import/actors2.csv --relationships import/roles2.csv --delimiter ";" --array-delimiter "|" --quote "'"
   
    

3.2 不同数据集定义相同节点

movies5a.csv.

movieId:ID,title,year:int 
tt0133093,"The Matrix",1999
   
    

sequels5a.csv.

movieId:ID,title,year:int 
tt0234215,"The Matrix Reloaded",2003 
tt0242653,"The Matrix Revolutions",2003
   
    

actors5a.csv.

personId:ID,name 
keanu,"Keanu Reeves" 
laurence,"Laurence Fishburne" 
carrieanne,"Carrie-Anne Moss"
   
    

执行语句:

neo4j_home$ bin/neo4j-admin import --nodes:Movie import/movies5a.csv --nodes:Movie:Sequel import/sequels5a.csv --nodes:Actor import/actors5a.csv
   
    

执行的时候,把movies5a.csv定义一个节点名字nodes:Movie
sequels5a.csv定义节点名字有两个::Movie:Sequel

3.3 定义关系名称以及关系属性

roles5b.csv.

:START_ID,role,:END_ID 
keanu,"Neo",tt0133093 
keanu,"Neo",tt0234215 
keanu,"Neo",tt0242653 
laurence,"Morpheus",tt0133093 
laurence,"Morpheus",tt0234215 
laurence,"Morpheus",tt0242653 
carrieanne,"Trinity",tt0133093
   
    

执行内容:

neo4j_home$ bin/neo4j-admin import --relationships:ACTED_IN import/roles5b.csv
   
    

其中,:ACTED_IN将关系名称定义为ACTED_IN;同时定义关系的属性也有role

3.4 拆分数据集上传提高效率

节点数据集,标题:movies4-header.csv.

movieId:ID,title,year:int,:LABEL
   
    

节点数据集,内容模块1:movies4-part1.csv.

tt0133093,"The Matrix",1999,Movie 
tt0234215,"The Matrix Reloaded",2003,Movie;Sequel
   
    

节点数据集,内容模块2:movies4-part2.csv.

tt0242653,"The Matrix Revolutions",2003,Movie;Sequel
   
    

关系数据集,标题:roles4-header.csv.

:START_ID,role,:END_ID,:TYPE
   
    

关系数据集,内容1:roles4-part1.csv.

keanu,"Neo",tt0133093,ACTED_IN 
keanu,"Neo",tt0234215,ACTED_IN
   
    

关系数据集,内容2:roles4-part2.csv.

laurence,"Morpheus",tt0242653,ACTED_IN 
carrieanne,"Trinity",tt0133093,ACTED_IN
   
    

执行:

neo4j_home$ bin/neo4j-admin import --nodes "import/movies4-header.csv,import/movies4-part1.csv,import/movies4-part2.csv" --relationships "import/roles4-header.csv,import/roles4-part1.csv,import/roles4-part2.csv"
   
    

标题与内容单独分开,然后由:标题,内容模块1,内容模块2,分块导入。

3.5 两个节点集拥有相同的字段

这个会比较经常出现,两个节点集合中,拥有相同字段,如果不设置,就会出现报错。
movies7.csv.

movieId:ID(Movie-ID),title,year:int,:LABEL 
1,"The Matrix",1999,Movie 
2,"The Matrix Reloaded",2003,Movie;Sequel 
3,"The Matrix Revolutions",2003,Movie;Sequel
   
    

其中,(Movie-ID),是将ID进行标记
actors7.csv.

personId:ID(Actor-ID),name,:LABEL 
1,"Keanu Reeves",Actor 
2,"Laurence Fishburne",Actor 
3,"Carrie-Anne Moss",Actor
   
    

roles7.csv.

:START_ID(Actor-ID),role,:END_ID(Movie-ID) 
1,"Neo",1 
1,"Neo",2 
1,"Neo",3 
2,"Morpheus",1 
2,"Morpheus",2 
2,"Morpheus",3 
3,"Trinity",1 
3,"Trinity",2 
3,"Trinity",3
   
    

执行:

neo4j_home$ bin/neo4j-admin import --nodes import/movies7.csv --nodes import/actors7.csv --relationships:ACTED_IN import/roles7.csv
   
    

在关联表中定义::START_ID(Actor-ID):END_ID(Movie-ID),来指定相应的ID。

3.6 错误信息跳过:错误的节点

错误的关系出现:
roles8a.csv.

:START_ID,role,:END_ID,:TYPE 
carrieanne,"Trinity",tt0242653,ACTED_IN 
emil,"Emil",tt0133093,ACTED_IN
   
    

譬如多出了节点,emil
此时执行:

neo4j_home$ bin/neo4j-admin import --nodes import/movies8a.csv --nodes import/actors8a.csv --relationships import/roles8a.csv --ignore-missing-nodes
   
    

其中的--ignore-missing-nodes就是跳过报错的节点,其中,错误信息会记录在bad.log之中:

InputRelationship: 
   source: roles8a.csv:11 
   properties: [role, Emil] 
   startNode: emil (global id space) 
   endNode: tt0133093 (global id space) 
   type: ACTED_IN 
 referring to missing node emil
   
    

3.7 错误信息跳过:重复节点

actors8b.csv.

 
personId:ID,name,:LABEL 
keanu,"Keanu Reeves",Actor 
laurence,"Laurence Fishburne",Actor 
carrieanne,"Carrie-Anne Moss",Actor 
laurence,"Laurence Harvey",Actor
   
    

在节点数据集actors8b.csv. 中,由重复的节点:laurence
需要执行:

neo4j_home$ bin/neo4j-admin import --nodes import/actors8b.csv --ignore-duplicate-nodes
   
    

其中,–ignore-duplicate-nodes就是重复节点忽略
会在bad.log之中显示报错:

Id 'laurence' is defined more than once in global id space, at least at actors8b.csv:3 and actors8b.csv:5
   
    
vv
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