Data searching method and device

Abstract

The embodiment of the invention discloses a data searching method and device. The method comprises the following steps that a data searching request is received; two data sheets needing splitting in a hashing mode are determined; information of the data sheets is sent to each slave node; corresponding relations, between hashed values and sheet fragmentation files, sent by the slave nodes are received; fragmentation is conducted on the hashed values to acquire hashed value fragments, and the slave nodes corresponding to the hashed value fragments are respectively determined; according to the relations between the hashed values and the sheet fragmentation files, all the nodes are controlled to transfer the sheet fragmentation files; connecting results, corresponding to each hashed value, sent by each slave node are received, and the data search request result is determined according to the connecting result. The data searching method and device can be used for acquiring the correct left outer join or right outer join result and further acquiring the correct data searching result when left outer join or right outer join is used for achieving data searching processing in an MPP distributed type data base system.

Description

technical field [0001] The invention relates to storage technology, in particular to a data query method and device. Background technique [0002] Currently, databases are generally used for data storage. When the user performs data query through the client, the client sends the query keyword entered by the user to the database, and the database performs data query according to the query keyword, and feeds back the query result to the client, and then the client displays the query result to the user. [0003] In currently commonly used stand-alone databases, processing methods such as left outer join and right outer join are often used for data query, and then the result of the data query is determined based on the processing results of the left outer join and right outer join. Among them, the processing objects of the left outer join and the right outer join are two tables, called the left table and the right table respectively, and the connection relationship between the...

AI Technical Summary

Problems solved by technology

[0008] However, if the above-mentioned left outer connection or right outer connection needs to be used in the data query of the MPP distributed database, for example, the left outer connection needs to be used, then when the database receives the user's data query request, the master node will send the data query request Split into multiple small data query tasks including left outer joins, each slave node performs left outer join according to the small data query tasks, and then the master node will not be able to obtain the correct left Outer join results, and thus the correct data query results cannot be obtained

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