Create Database baseball;14.alter table tablename change oldColumn newColumn column_type 修改列的名称和类型 alter table yangsy CHANGE product_no phone_no string 15.导入.sql文件中的sql spark-sql --driver-class-path /home/hadoop/hive/lib/mysql-connector-java-5.1.30-bin.jar -f testsql.sql i...
这两个参数和上面的spark.sql.files.ignoreCorruptFiles很像,但是区别是很大的。在spark进行DataSource表查询时候spark.sq.files.*才会生效,而spark如果查询的是一张hive表,其会走HadoopRDD这条执行路线。 所以就会出现,即使你设置了spark.sql.files.ignoreMissingFiles的情况下,仍然报FileNotFoundException的情况,异常栈...
Spark SQL里面有很多的参数,而且这些参数在Spark官网中没有明确的解释,可能是太多了吧,可以通过在spark-sql中使用set -v 命令显示当前spark-sql版本支持的参数。
SQL 主要由Projection(filedA,fieldB,fieldC),DataSource(tableA)和Filter(fieldA>10)三个部分组成,分别对应 SQL 查询过程中的Result,DataSource和Operation: 实际的 SQL 执行顺序过程是按照 Opertaion->DataSouece->Result 的顺序,刚好与 SQL 的语法刚好相反,具体包括: 首先进行词法和语法 Parse,对输入的 SQL ...
defexecute(plan:TreeType):TreeType={varcurPlan=planvalqueryExecutionMetrics=RuleExecutor.queryExecutionMetervalplanChangeLogger=newPlanChangeLogger[TreeType]()valtracker:Option[QueryPlanningTracker]=QueryPlanningTracker.getvalbeforeMetrics=RuleExecutor.getCurrentMetrics()valenableValidation=SQLConf.get.getConf(SQ...
TRANSACTIONEND) { continue; } RowChange rowChage = null; try { rowChage = RowChange.parseFrom(entry.getStoreValue()); } catch (Exception e) { throw new RuntimeException("ERROR ## parser of eromanga-event has an error , data:" + entry.toString(), e); } EventType eventType = row...
命名空间: Microsoft.Spark.Sql.Types 程序集: Microsoft.Spark.dll 包: Microsoft.Spark v1.0.0 表示数值类型。C# 复制 public abstract class NumericType : Microsoft.Spark.Sql.Types.AtomicType继承 Object DataType AtomicType NumericType 派生 Microsoft.Spark.Sql.Types.FractionalType Microsoft.Spark....
SparkSql DDL Mayer 1、背景 最近公司为了降本,在做presto sql 到spark sql的任务迁移(体力活 ),作为一个两年多来一直在用presto的sql boy,因为presto本身是针对adhoc场景,所以在平时建表的时候都是简单粗暴的create table table_name as 、 insert into table_name 等等, 最近上线了spark之后,发现了spark在...
importorg.apache.spark.sql._importorg.apache.spark.sql.types._valpeopleSchema =StructType(Array(StructField("Name",StringType, nullable =false),StructField("Age",DoubleType, nullable =false),StructField("Occupation",StringType, nullable =false),StructField("Date of birth",StringType, nullable =...
A row is nothing more than a record of data. Each record in a DataFrame must be of typeRow, as we can see when we collect the following DataFrames. We can create these rows manually from SQL, from Resilient Distributed Datasets (RDDs), from data sources, or manually from scratch. Here...