1、 set hive.auto.convert.join = true; mapJoin的主要意思就是,当链接的两个表是一个比较小的表和一个特别大的表的时候,我们把比较小的table直接放到内存中去,然后再对比较大的表格进行map操作。join就发生在map操作的时候,每当扫描一个大的table中的数据,就要去去查看小表的数据,哪条与之相符,继而进行连接。
hive.ignore.mapjoin.hint=true;#虽然现在可以自动转化mapjoin,但还是建议设成true,可以在需要特殊处理人为转化为mapjoin。 hive.auto.convert.join=true; hive.mapjoin.smalltable.filesize=250000000; N-way join: hive.auto.convert.join.noconditionaltask=true;#开启多路join加载到map中的开关。 hive.auto.conve...
odps.sql.mapjoin.memory.max The size of small tables that are read to the memory when the MAPJOIN statement is executed. Unit: MiB. Valid values: 0 MiB to 8192 MiB. JOIN SQL Session odps.sql.python.version The Python version on which SQL statements are executed. ...
hive.mapjoin.optimized.hashtable 是Hive 中的一个配置参数,用于控制在进行 MapJoin(也称为小表广播连接)时是否使用优化的哈希表。MapJoin 是一种优化技术,它通过将小表的数据分发到所有执行 Map 任务的节点上,以减少连接时的数据传输量,从而提高查询性能。当启用优化的哈希表时,Hive 会尝试使用更高效的哈希表实...
Map http drive Mapped File High usage memory Mapped File memory consumed Mapped network drive prompt for new credentials Mapping more than home folder to a user account Match PDO to StoragePool PhysicalDisk Max ARP cache size Max connections to a share folder Maximum # of CPU cores in Editions...
Get Process Memory Usage Get process tree Get product keys of local and remote systems Get Property Value only -ExpandProperty returns multiple options? Get remote computer name Get remote logged on user with powershell Get Remote Machine Name and SerialNumber Get Richtextbox text length get samac...
包路径:org.apache.hadoop.hive.ql.parse.QBJoinTree类名称:QBJoinTree方法名:setMapSideJoin QBJoinTree.setMapSideJoin介绍 暂无 代码示例 代码示例来源:origin: apache/hive joinTree.setMapSideJoin(true); 代码示例来源:origin: apache/drill joinTree.setMapSideJoin(true); 代码示例来源:origin: apache/...
类名称:QBJoinTree方法名:setMapAliases QBJoinTree.setMapAliases介绍 暂无 代码示例 代码示例来源:origin: apache/hive target.setMapAliases(mapAliases); 代码示例来源:origin: apache/drill target.setMapAliases(mapAliases); 代码示例来源:origin: apache/hive joinTree.setMapAliases(mapAliases); 代码示例来源...
Map http drive Mapped File High usage memory Mapped File memory consumed Mapped network drive prompt for new credentials Mapping more than home folder to a user account Match PDO to StoragePool PhysicalDisk Max ARP cache size Max connections to a share folder Maximum # of CPU cores in Editions...
代码示例来源:origin: apache/hive filters.add(new ArrayList<ASTNode>()); jT.setFilters(filters); jT.setFilterMap(new int[2][]); 代码示例来源:origin: apache/drill filters.add(new ArrayList<ASTNode>()); joinTree.setFilters(filters); joinTree.setFilterMap(new int[2][]); 代码示例来源:origi...