Andrej Pashchenko
@andrejsql.bsky.social
📤 197
📥 98
📝 17
Data Engineer, Oracle Ace Pro ♠ blog.sqlora.com
Learning from mistakes is important. Better: learn from others' mistakes. Even better: today we can learn from
@danischnider.bsky.social
's ones
#doag2025
5 days ago
0
5
2
reposted by
Andrej Pashchenko
SQLDaily
19 days ago
Storing UUIDs as RAW values is more efficient than strings But RAW can lead to implicit conversions => poor row estimates If you're stuck with string comparisons
@andrejsql.bsky.social
shows how to improve row estimates with Extended stats Virtual columns
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Fix Optimizer Estimate Issues from Implicit Conversions #JoelKallmanDay
Learn how implicit RAW-to-VARCHAR2 conversions in Oracle break histograms, hurt optimizer estimates, and how to fix them safely.
https://buff.ly/NeP8x2E
1
5
1
The long way of
#JSON
in
#Oracle
, from 12.1.0.2 until today. Now starting with 23ai and still 15 minutes left. Not bad! You can do it!
#HrOUG2025
#HrOUG25
add a skeleton here at some point
about 1 month ago
1
4
0
reposted by
Andrej Pashchenko
Philipp Salvisberg
about 1 month ago
Tennis before the first session on day 3 of HrOUG with team „Awesome“ and „OMG“. It was great fun. Thanks!
#HrOUG25
#HrOUG2025
0
5
2
reposted by
Andrej Pashchenko
Piet de Visser
about 1 month ago
#joelkallmanday
We tend to forget that troubleshooting is mainly just about Clear and Calm thinking..
pdvfirstblog.blogspot.com/2025/10/simp...
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Simplicity, Troubleshooting, #JoelKallmanday
TL;DR: You don't have to be a genius to solve problems. And there is no shame in not-knowing or not understanding all the geeky details. Ma...
https://pdvfirstblog.blogspot.com/2025/10/simplicity-troubleshooting.html
0
5
4
reposted by
Andrej Pashchenko
Øyvind Isene
about 1 month ago
New blogpost
enesi.no/2025/10/uuid...
#JoelKallmanDay
#oracle
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UUIDs in Oracle Database
UUIDs are useful, especially when you expose data in REST APIs, but there are cases where you may want to stick to the good old sequence-based primary key. UUIDs in Oracle Database #JoelKallmanDay UUI...
https://enesi.no/2025/10/uuids-in-oracle-database/
0
4
4
New post for
#JoelKallmanDay
! Ever wondered why the Oracle Optimizer sometimes ignores your histograms? Implicit data type conversions might be to blame. Here’s how to fix it without touching your SQL and with minimal schema impact.
#Oracledatabase
blog.sqlora.com/en/fix-optim...
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Fix Optimizer Estimate Issues from Implicit Conversions #JoelKallmanDay
Learn how implicit RAW-to-VARCHAR2 conversions in Oracle break histograms, hurt optimizer estimates, and how to fix them safely.
https://blog.sqlora.com/en/fix-optimizer-estimate-issues-from-implicit-conversions-joelkallmanday/
about 1 month ago
0
8
1
Honored to speak at
#HROUG2025
– celebrating its 30th anniversary in amazing Rovinj! 🎉 Huge thanks to the organizers for keeping this fantastic community going for 30 years! 🙏 Let’s put some old SQL myths to the test together!
#Oracle
#SQL
#Optimizer
#Accenture
#OracleAce
about 2 months ago
0
8
1
How do I get the test data these days? My
#Accenture
colleague
@cgohmannde.bsky.social
explains.
#makeit2025
6 months ago
0
2
0
Who will win?
@andreakennel.bsky.social
,
@danischnider.bsky.social
or
#ChatGPT
? We'll see.
6 months ago
0
4
2
reposted by
Andrej Pashchenko
Dani Schnider
6 months ago
I finish the first day of
#MakeIT2025
like I started it: with a session of
@andrejsql.bsky.social
. This time he talks about parameterized views in Oracle
1
5
1
How can we help the Oracle optimizer to do better with function calls?
@danischnider.bsky.social
explains.
#makeit2025
6 months ago
0
3
1
reposted by
Andrej Pashchenko
6 months ago
After the keynote at
#MakeITConf
, my Accenture colleague
@andrejsql.bsky.social
shared some interesting insights of table merging.
@oracleace.bsky.social
0
6
1
reposted by
Andrej Pashchenko
Dani Schnider
6 months ago
Conferences are always a chance to see my former colleagues of Trivadis again:
@andrejsql.bsky.social
talking about table merging at
#MakeIT2025
0
2
1
MERGE ... RETURNING is now supported in Oracle 23ai. In my view, it deserves more visibility in the documentation — it wasn’t easy to find. Even LLMs still claim it doesn’t exist (some go as far as inventing error codes). Read more:
#Oracle23ai
#SQL
#MERGE
#OracleDB
blog.sqlora.com/en/merge-and...
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MERGE and DML RETURNING clause in Oracle 23ai
Oracle 23ai finally supports MERGE … RETURNING! A long-awaited feature, but still hard to find in the docs.
https://blog.sqlora.com/en/merge-and-dml-returning-clause-in-oracle-23ai/
7 months ago
0
5
0
Ten years after my first post on the quirks of MERGE and ORA-30926, I took a fresh look at how Oracle 23ai handles it. Clearer error messages, improved diagnostics, and fewer unnecessary restarts. Read the new blog post
#Oracle23ai
#SQL
#MERGE
@oracleace.bsky.social
blog.sqlora.com/en/ora-30926...
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ORA-30926 in Oracle 23ai: What’s Changed?
Explore how Oracle 23ai improves MERGE behavior and error handling, replacing vague ORA-30926 message with clearer, smarter diagnostics.
https://blog.sqlora.com/en/ora-30926-in-oracle-23ai-whats-changed/
7 months ago
0
2
0
Happy to share my new Oracle Certified AI Vector Search Professional certification! BTW, it is free until May 15 2025
#Oraclecertified
#ConvergedDatabase
catalog-education.oracle.com/pls/certview...
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Oracle AI Vector Search Certified Professional
he Oracle AI Vector Search Professional Certification is designed for Oracle DBAs, AI engineers, and cloud developers to unlock the potential of Oracle Database 23ai to build AI-driven applications. T...
https://catalog-education.oracle.com/pls/certview/sharebadge?id=E622E2027D78169A521C4ECD7DD474C69E2AC725803C257C147DD8DB50120553
9 months ago
1
4
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Did you know that refreshing HCC-compressed materialized views with atomic_refresh=true can multiply storage usage over time? Small details can have massive impacts. Read the new blog post.
#Exadata
#Oracle
#HCC
@oracleace.bsky.social
blog.sqlora.com/en/when-comp...
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When Compression Expands: The Hidden Pitfalls of HCC
This post explores the behavior of Hybrid Columnar Compression (HCC) in Oracle Exadata while refreshing materialized views with atomic_refresh=true.
https://blog.sqlora.com/en/when-compression-expands-the-hidden-pitfalls-of-hcc/
11 months ago
0
3
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The same topic, the same
@danischnider.bsky.social
, but something has changed, the stage dimension perhaps? Note: stage dimension is not a new term in data warehousing, Dani is speaking about 😃
add a skeleton here at some point
12 months ago
1
3
0
Excited to speak at
#UKOUGDiscover24
! Do you also believe that collecting statistics in a data warehouse is not a ‘one size fits all’ approach? And that a targeted approach is part of your role as a data engineer? Join my session on 2 December at 16:00. See you there!
ukoug.org/page/UKOUGCo...
12 months ago
0
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@danischnider.bsky.social
explains the performance of views on the big stage of the
#DOAG2024
about 1 year ago
0
6
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Mentioned you, your blog und linked to your package SQM_UTIL,
@stewashton.bsky.social
. Such package is a must have if you consider using SQL Macros. Thank you.
add a skeleton here at some point
about 1 year ago
1
4
0
The wait is over:
#DOAG2024
starts tomorrow in Nuremberg. Want to learn about some advanced techniques and concepts around the practical use cases of
#SQLMacros
in
#oracledatabase
? Join me in the very first slot at 8:30
about 1 year ago
0
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