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I have a delta table that is partitioned by Year, Date and month. I'm trying to merge data to this on all three partition columns + an extra column (an ID). My merge statement is below:MERGE INTO delta.<path of delta table> oldData
using df newData ...
Isn't the suggested idea only filtering the input dataframe (resulting in a smaller amount of data to match across the whole delta table) rather than prune the delta table for relevant partitions to scan?
Hey as previously stated you could drop the duplicates of the columns that contain the said duplicates(code you can find online pretty easily), I have had this problem myself and it came when creating a temporary view from a dataframe, the dataframe ...
OverviewTo update our Data Warehouse tables, we have tried two methods: "CREATE OR REPLACE" and "MERGE". With every query we've tried, "MERGE" is slower.My question is this: Has anyone successfully gotten a "MERGE" to perform faster than a "CREATE OR...
Hi @Graham Can you please try Low Shuffle Merge [LSM] and see if it helps? LSM is a new MERGE algorithm that aims to maintain the existing data organization (including z-order clustering) for unmodified data, while simultaneously improving performan...
I have 1 delta table that I continuously append events into, and a 2nd delta table that I continuously merge into (streamed from the 1st table) that has unique ID's where properties are updated from the events (An ID represents a unique thing that ge...
We are having some issues with merge performance, so I went and read a bit in the documentation, I found this section:https://docs.databricks.com/delta/tune-file-size.html#autotune-file-size-based-on-workload"Databricks recommends setting the table p...
I am using the following query to make an upsert:MERGE INTO my_target_table AS target
USING (SELECT MAX(__my_timestamp) AS checkpoint FROM my_source_table) AS source
ON target.name = 'some_name'
AND target.address = 'some_address'
WHEN MATCHED AN...
I was using a view for my_source_table, once I changed that to be a table the issue stoped.That unblocked me, but I think Databricks has a bug with using MERGE INTO from a VIEW
from 10.4 LTS version we have low shuffle merge, so merge is more faster. But what about MERGE INTO function that we run in sql notebook of databricks. Is there any performance difference when we use databrciks pyspark ".merge" function vs databricks...
Hi @Roshan RC Thank you for posting your question in our community! We are happy to assist you.To help us provide you with the most accurate information, could you please take a moment to review the responses and select the one that best answers you...
Hi @Prashant Joshi Hope everything is going great.Just wanted to check in if you were able to resolve your issue. If yes, would you be happy to mark an answer as best so that other members can find the solution more quickly? If not, please tell us s...
Hi I am trying to use the SQL Merge statement on databricksMERGE INTO targetUSING sourceON source.key = target.keyWHEN MATCHED UPDATE SET *WHEN NOT MATCHED INSERT *WHEN NOT MATCHED BY SOURCE DELETEThis is failing with the error [PARSE_SYNTAX_ERROR...
I was missing the THEN before UPDATE, INSERT and DELETE. This keyword is missing from the documentation on Databricks https://learn.microsoft.com/en-us/azure/databricks/delta/mergeIt now works. Thanks
Coming from MS SQL background, I'm trying to write a query in Spark SQL that simply update a column value of table A (source table) by INNER JOINing a new table B with a filter.MS SQL query looks like this:UPDATE T
SET T.OfferAmount = OSE.EndpointEve...
Posting answer to my question:
MERGE into TempOffer VIEW
USING OfferSeq OSE ON VIEW.OfferId = OSE.OfferID AND OSE.OfferId = 1
WHEN MATCHED THEN UPDATE set VIEW.OfferAmount = OSE.EndpointEventAmountValue;
Since databricks runtime 12.1 "WHEN NOT MATCHED BY SOURCE" was added to MERGE syntax. For example, using that option, we can quickly delete all target rows which doesn't match any source.
I had been trying to upsert rows into a table in Azure Blob Storage (ADLS Gen 2) based on two partitions (sample code below). insert overwrite table new_clicks_table partition(client_id, mm_date)
select
click_id
,user_id
,click_timestamp_gmt
,ca...
I have a Merge into statement that I use to update existing entries or create new entries in a dimension table based on a natural business key.When creating new entries I would like to also create a unique uuid for that entry that I can use to crossr...
you might wanna look into an identity column, which is possible now in delta lake.https://www.databricks.com/blog/2022/08/08/identity-columns-to-generate-surrogate-keys-are-now-available-in-a-lakehouse-near-you.html
Hi there,I am using apply_changes (aka. Delta Live Tables Change Data Capture) and it works fine. However, it seems to automatically create a secondary table in the database metastore called _apply_storage_changes_{tableName}So for every table I use ...
Hi guys,I'm trying to use uuid in the merge but I always get an error...import uuid
(
df_events.alias("events").merge(
source = df_updates.alias("updates"),
condition = "events.cod = updates.cod and events.num = updates.num"
).whenMatch...
Hi @William Scardua Hope all is well! Just wanted to check in if you were able to resolve your issue and would you be happy to share the solution or mark an answer as best? Else please let us know if you need more help. We'd love to hear from you.Th...
