Truncate Table Command

Http://www.aliyun.com/zixun/aggregation/13713.html ">hbase is a distributed, column-oriented open source database, rooted in a Google paper BigTable: A distributed storage system of structured data. HBase is an open-source implementation of Google BigTable, using Hadoop HDFs as its file storage system, using Hadoop mapreduce to handle ...

We want to do not only write SQL, but also to do a good performance of the SQL, the following for the author to learn, extract, and summarized part of the information to share with you! (1) Select the most efficient table name order (valid only in the Rule-based optimizer): The ORACLE parser processes the table names in the FROM clause in Right-to-left order, and the last table in the FROM clause (the underlying table driving tables) is processed first, In the case where multiple tables are included in the FROM clause, you must select the table with the least number of records as the underlying table. If...

The complete collection of SQL statement operations deserves to be permanently stored the following statements are part of the MSSQL statement and are not available in Access. SQL classification: ddl-data Definition language (create,alter,drop,declare) dml-Data Manipulation Language (Select,delete,update,insert) dcl-Data Control Language (Grant,revoke, Commit,rollback first, briefly introduce the basic statement: 1, Description: Create number ...

Function Description: Create or modify a stored file, or extract files from a saved file. Syntax:ar[-dmpqrtx][cfossuvv][a< member file >][b< member file >][i< member file >][file [member file] Supplemental Note: AR allows you to assemble many files and become a single, stored file. In a saved file, all member files retain their original attributes and permissions. Parameter: Instruction parameter &http://www.aliyun ....

1. HQueue profile HQueue is a set of distributed, persistent message queues developed by hbase based on the search web crawl offline Systems team. It uses htable to store message data, HBase coprocessor to store the original keyvalue data in the message data format, and encapsulates the HBase client API for message access based on the HQueue client API. HQueue can be effectively used in the need to store time series data, as MAPR ...