Programmer Think

2021SC@SDUSC catalogue Overview & & Review Code analysis: method of generating QB Summary: Overview & & Review As for the generation of QB by semantic parsing AST, we have always focused on code reading, and the content is scattered and split. Now, after reviewing the flow chart of HIVE compiler, we can see that semantic ...

Preface The installation of Hive needs to be built on top of Hadoop (similar to Hbase), and two other blogs by the author can be referenced for standalone and pseudo-distributed installations of Hadoop: Detailed tutorial on single installation of Hadoop under Ubuntu (with required installation package downloads)Detailed tutorial on pseu ...

preface Recently, a course experiment needs to be configured with the environment shown in the title, so the author takes this opportunity to use docker to build a returnable container experiment environment to complete the experiment, and also records some errors encountered in the construction process. 1, Environmental description ...

JAVA----API 1, API 1. Basic use of scanner API Explanation: The full name is application programming interface(Application Programming Interface), Originally meant to mean JDK Various classes and interfaces provided For example: Scanner Get string public String nextLine(); Get the string entered by the user and get the whole line of data. ...

2021SC@SDUSC catalogue summary Semantic analyzer class analysis: ① From analyzeInternal(ASTNode ast) to genResolvedParseTree(ASTNode, planercontext) summary Earlier, I made a simple analysis of the basesemanticananalyzer class and learned that this class is the base class of each semantic analyzer, and its derived subclasses include sema ...

This paper combs and summarizes the parameter meaning and use of spark.sql.hive.caseSensitiveInferenceMode of spark 1. Parameter meaning Spark 2.1.1 introduces a new configuration item: spark.sql.hive.caseSensitiveInferenceMode. The default value is NEVER_INFER, maintain behavior consistent with spark 2.1.0. However, Spark 2.2.0 changes the de ...

Author: duktig Blog: https://duktig.cn (first article) Excellent still work hard. May you enjoy what you give and enjoy what you get. See github knowledge base for more articles: https://github.com/duktig666/knowledge background After learning Hadoop, do you feel that writing a MapReduce program is very complex, and it requires a lot ...

Author: duktig Blog: https://duktig.cn (first article) Excellent still work hard. May you enjoy what you give and enjoy what you get. See github knowledge base for more articles: https://github.com/duktig666/knowledge background After learning Hadoop, do you feel that writing a MapReduce program is very complex, and it requires a lot ...

3, Query operation ▎ [3.1] which databases in hive are queried show databases; Before creating other databases, hive will provide a default database for us to use default   When operating HiveQL, all operations are performed in the default data without specifying the database. The database name and table name of hive are not case sensi ...

1. Writing order -select -from -join -on -where -group by -having -order by -limit 2. Execution sequence - from - where - join - on - select - group by - having - distinct - order by - limit - union / union on 3.Hive relational operator [common] !=Not equal to<> Not equal to==Wait for=be equal to+plus-reduce*ride/ex ...