SQL Copy -- Multiple MATCHED and NOT MATCHED clauses with schema evolution enabled. > MERGE WITH SCHEMA EVOLUTION INTO target USING source ON source.key = target.key WHEN MATCHED THEN UPDATE SET * WHEN NOT MATCHED THEN INSERT * WHEN NOT MATCHED BY SOURCE THEN DELETE ...
可以将MERGE INTO用于复杂的操作,如删除重复数据、更新插入更改数据、应用 SCD 类型 2 操作等。请参阅使用合并以更新插入的方式插入到 Delta Lake 表中获取一些示例。 WHEN MATCHED SQL复制 -- Delete all target rows that have a match in the source table.>MERGEINTOtargetUSINGsourceONtarget.key = source...
可以将MERGE INTO用于复杂的操作,如删除重复数据、更新插入更改数据、应用 SCD 类型 2 操作等。请参阅使用合并以更新插入的方式插入到 Delta Lake 表中获取一些示例。 WHEN MATCHED SQL复制 -- Delete all target rows that have a match in the source table.>MERGEINTOtargetUSINGsourceONtarget.key = source...
> MERGE INTO target USING source ON target.key = source.key WHEN NOT MATCHED BY TARGET AND source.created_at > now() - INTERVAL “1” DAY THEN INSERT (created_at, value) VALUES (source.created_at, DEFAULT) WHEN NOT MATCHED BY SOURCE Copy SQL -- Delete all target rows that have no...
适用于 Databricks SQL、Databricks Runtime 12.2 及更高版本错误类是错误条件特有的描述性、可读性字符串。可以使用错误类以编程方式处理应用程序中的错误,而无需分析错误消息。这是Azure Databricks 返回的常见命名错误条件的列表。Databricks Runtime 和 Databricks SQLAGGREGATE...
Streaming table 是物化视图的一种增强,是在 live table 的基础上对流计算和增量处理做了特殊的优化,这点对理解 DLT 的流批一体至关重要,DLT 的流表只能应用于 append-only 的数据集,如果是 CDC 数据,Databricks 提供了一个 APPLY CHANGES INTO 的语法来代替复杂的 Merge into SQL,考虑使用流表的情况[2]: ...
delta lake的API提供了由用户指定log record ID的机制来读取特定版本的数据,使用类似"AS OF timestamp" 或 "VERSION AS OF commit_id"的SQL语法来完成。同时使用如下merge操作来用老版本修复不正确的数据: MERGE INTO mytable target USING mytable TIMESTAMP AS OF <old_date> source ON source.userId = ...
在使用DML error log之前，针对单行处理首选的办法是使用批量SQL FORALL 的SAVE EXCEPTIONS子句。而在...
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...
> MERGE INTO target USING source ON target.key = source.key WHEN NOT MATCHED BY TARGET AND source.created_at > now() - INTERVAL “1” DAY THEN INSERT (created_at, value) VALUES (source.created_at, DEFAULT) WHEN NOT MATCHED BY SOURCE Copy SQL -- Delete all target rows that have no...