importio.delta.tables._valdeltaTable =DeltaTable.forName(spark,"source_table") deltaTable.clone(target="target_table", isShallow=true, replace=false)// clone the source at latest versiondeltaTable.cloneAtVersion(version=1, target="target_table", isShallow=true, replace=false)// clone the sou...
还可以选择使用 Delta Lake API 来执行流式 upsert,如以下示例所示: Scala Scala importio.delta.tables.*valdeltaTable =DeltaTable.forName(spark,"table_name")// Function to upsert microBatchOutputDF into Delta table using mergedefupsertToDelta(microBatchOutputDF:DataFrame, batchId:Long) { deltaTable....
import io.delta.tables._ import org.apache.spark.sql.functions._ val deltaTablePeople = DeltaTable.forName(spark, "people10m") val deltaTablePeopleUpdates = DeltaTable.forName(spark, "people10mupdates") val dfUpdates = deltaTablePeopleUpdates.toDF() deltaTablePeople .as("people") .merge( df...
每天做ETL数据清洗,做表的merge操作 ,delta表结构为: %sql CREATE TABLE IF NOT EXISTS delta.delta_{table_name}( id bigint, uname string, dom string, email string, update timestamp, created timestamp USING delta LOCATION '---/delta/' %sql MERGE INTO delta.delta_{table_name} AS A USING (...
使用UDF 函数定义流数据写入 Delta Lake 的 Merge 规则 %spark import org.apache.spark.sql._ import io.delta.tables._ // Function to upsert `microBatchOutputDF` into Delta table using MERGE def upsertToDelta(microBatchOutputDF: DataFrame, batchId: Long) { // Set the dataframe to view name mi...
.format("delta") .mode("overwrite") .partitionBy("par") .saveAsTable("delta_merge_into") Then merge a DataFrame into the Delta table to create a table calledupdate: %scala val updatesTableName = "update" val targetTableName = "delta_merge_into" ...
低随机排列合并:低随机排列合并提供了MERGE的优化实现,可为大多数常见工作负载提供更好的性能。 此外,它还保留了现有的数据布局优化,例如对未修改数据的进行Z 排序。 管理数据时效性 在每个查询开头,Delta 表自动更新到最新版本的表。 当命令状态报告Updating the Delta table's state时,可以在笔记本中观察到此过程...
delta_df=spark.read.format("delta").load("/path/to/delta/lake") delta_df.show() 1.2.2示例:使用DeltaLake进行数据更新 DeltaLake支持使用MERGE语句来更新数据,这在处理大量数据时非常有 用,可以避免全表扫描和数据重写。 #创建一个新的DataFrame,包含更新的数据 ...
还可以选择使用 Delta Lake API 来执行流式 upsert,如以下示例所示: Scala Scala importio.delta.tables.*valdeltaTable =DeltaTable.forName(spark,"table_name")// Function to upsert microBatchOutputDF into Delta table using mergedefupsertToDelta(microBatchOutputDF:DataFrame, batchId:Long) { deltaTable....
Merges a set of updates, insertions, and deletions based on a source table into a target Delta table.This statement is supported only for Delta Lake tables.This page contains details for using the correct syntax with the MERGE command. See Upsert into a Delta Lake table using merge for m...