From 4e1284af85e1ca0ac473fda6790e251c052c8dc3 Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Fri, 11 Apr 2025 16:51:30 +0200 Subject: [PATCH 1/8] Create subquery-replication-boarder.md --- .../subquery-replication-boarder.md | 24 +++++++++++++++++++ 1 file changed, 24 insertions(+) create mode 100644 Support-and-Services/subquery-replication-boarder.md diff --git a/Support-and-Services/subquery-replication-boarder.md b/Support-and-Services/subquery-replication-boarder.md new file mode 100644 index 00000000..0a0fb2f9 --- /dev/null +++ b/Support-and-Services/subquery-replication-boarder.md @@ -0,0 +1,24 @@ +# Replication border and Subquery replication border + +## Background + +Concept of the replication boarder and corresponding db parameter `-soft_replicationborder_in_numrows` described here: +[Best Practices](https://docs.exasol.com/db/latest/performance/best_practices.htm?Highlight=replication) +[Replication border in Exasol 6.1](https://exasol.my.site.com/s/article/Replication-border-in-Exasol-6-1?language=en_US) + +But `-soft_replicationborder_in_numrows` only works for persistent tables, for temp tables and materializations it doesn't. +However, there is another undocumented parameter `-subqueryreplicationboarder` which plays exactly the same role but only for subquery's temp tables. + +* When the Optimizer decides if a subquery or materialized table should be replicated, it uses the subquery replication border parameter. It also defaults to 100000 and can be explicitly altered by using the command-line parameter `-subqueryreplicationborder`, same way as with the standard replication border. +* Increasing this parameter can lead to higher DBRAM usage, which may alter the system's behavior. In some cases, this can result in excessive memory consumption and overall system slowdown. Therefore, please adjust this setting with caution. +* IMPORTANT: This is an undocumented parameter, so we cannot guarantee that its behavior will remain unchanged in the future. However, it has been confirmed that there are no plans to modify this behavior in version 8. +* In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM\SESSION command instead of db command-line parameter. But for the `-subqueryreplicationboarder` the same is not provided. So the only way of changing it remains db command-line parameter. + +## How to adjust SubqueryReplication border +The replication borders can be modified through extra database parameters: + +```sh +-subqueryreplicationboarder= [default is 100000 rows] +``` + +*We appreciate your input! Share your knowledge by contributing to the Knowledge Base directly in [GitHub](https://github.com/exasol/public-knowledgebase).* From ccbcc72fb0f528c021d44de88633cafb6c4f6c4e Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Fri, 11 Apr 2025 16:52:19 +0200 Subject: [PATCH 2/8] Update subquery-replication-boarder.md --- Support-and-Services/subquery-replication-boarder.md | 1 + 1 file changed, 1 insertion(+) diff --git a/Support-and-Services/subquery-replication-boarder.md b/Support-and-Services/subquery-replication-boarder.md index 0a0fb2f9..305c7294 100644 --- a/Support-and-Services/subquery-replication-boarder.md +++ b/Support-and-Services/subquery-replication-boarder.md @@ -15,6 +15,7 @@ However, there is another undocumented parameter `-subqueryreplicationboarder` w * In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM\SESSION command instead of db command-line parameter. But for the `-subqueryreplicationboarder` the same is not provided. So the only way of changing it remains db command-line parameter. ## How to adjust SubqueryReplication border + The replication borders can be modified through extra database parameters: ```sh From 684567fe234be2a2aca8d69553f6fdfefa7ff6ae Mon Sep 17 00:00:00 2001 From: Stefan Reich Date: Mon, 14 Apr 2025 09:05:51 +0200 Subject: [PATCH 3/8] adding spelling fixes, formatting and v8 changelog link --- ...rder.md => subquery-replication-border.md} | 22 ++++++++++--------- 1 file changed, 12 insertions(+), 10 deletions(-) rename Support-and-Services/{subquery-replication-boarder.md => subquery-replication-border.md} (52%) diff --git a/Support-and-Services/subquery-replication-boarder.md b/Support-and-Services/subquery-replication-border.md similarity index 52% rename from Support-and-Services/subquery-replication-boarder.md rename to Support-and-Services/subquery-replication-border.md index 305c7294..eafff683 100644 --- a/Support-and-Services/subquery-replication-boarder.md +++ b/Support-and-Services/subquery-replication-border.md @@ -1,25 +1,27 @@ -# Replication border and Subquery replication border +# Subquery Replication Border ## Background -Concept of the replication boarder and corresponding db parameter `-soft_replicationborder_in_numrows` described here: -[Best Practices](https://docs.exasol.com/db/latest/performance/best_practices.htm?Highlight=replication) -[Replication border in Exasol 6.1](https://exasol.my.site.com/s/article/Replication-border-in-Exasol-6-1?language=en_US) +Concept of the replication border and corresponding db parameter `-soft_replicationborder_in_numrows` described here: + +- [Best Practices](https://docs.exasol.com/db/latest/performance/best_practices.htm?Highlight=replication) +- [Replication border in Exasol 6.1](https://exasol.my.site.com/s/article/Replication-border-in-Exasol-6-1) +- [Replication border in Exasol 8](https://exasol.my.site.com/s/article/Changelog-content-16000) But `-soft_replicationborder_in_numrows` only works for persistent tables, for temp tables and materializations it doesn't. -However, there is another undocumented parameter `-subqueryreplicationboarder` which plays exactly the same role but only for subquery's temp tables. +However, there is another undocumented parameter `-subqueryreplicationborder` which plays exactly the same role but only for subquery's temp tables. -* When the Optimizer decides if a subquery or materialized table should be replicated, it uses the subquery replication border parameter. It also defaults to 100000 and can be explicitly altered by using the command-line parameter `-subqueryreplicationborder`, same way as with the standard replication border. -* Increasing this parameter can lead to higher DBRAM usage, which may alter the system's behavior. In some cases, this can result in excessive memory consumption and overall system slowdown. Therefore, please adjust this setting with caution. -* IMPORTANT: This is an undocumented parameter, so we cannot guarantee that its behavior will remain unchanged in the future. However, it has been confirmed that there are no plans to modify this behavior in version 8. -* In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM\SESSION command instead of db command-line parameter. But for the `-subqueryreplicationboarder` the same is not provided. So the only way of changing it remains db command-line parameter. +- When the Optimizer decides if a subquery or materialized table should be replicated, it uses the subquery replication border parameter. It also defaults to 100000 and can be explicitly altered by using the command-line parameter `-subqueryreplicationborder`, same way as with the standard replication border. +- Increasing this parameter can lead to higher DBRAM usage, which may alter the system's behavior. In some cases, this can result in excessive memory consumption and overall system slowdown. Therefore, please adjust this setting with caution. +- IMPORTANT: This is an undocumented parameter, so we cannot guarantee that its behavior will remain unchanged in the future. However, it has been confirmed that there are no plans to modify this behavior in version 8. +- In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM\SESSION command instead of db command-line parameter. But for the `-subqueryreplicationborder` the same is not provided. So the only way of changing it remains db command-line parameter. ## How to adjust SubqueryReplication border The replication borders can be modified through extra database parameters: ```sh --subqueryreplicationboarder= [default is 100000 rows] +-subqueryreplicationborder= [default is 100000 rows] ``` *We appreciate your input! Share your knowledge by contributing to the Knowledge Base directly in [GitHub](https://github.com/exasol/public-knowledgebase).* From 821760008f0ceed655849d0c3d9240e12df75403 Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Mon, 28 Apr 2025 13:44:01 +0200 Subject: [PATCH 4/8] Update Support-and-Services/subquery-replication-border.md Co-authored-by: allipatev <58830344+allipatev@users.noreply.github.com> --- Support-and-Services/subquery-replication-border.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Support-and-Services/subquery-replication-border.md b/Support-and-Services/subquery-replication-border.md index eafff683..c09cf000 100644 --- a/Support-and-Services/subquery-replication-border.md +++ b/Support-and-Services/subquery-replication-border.md @@ -4,7 +4,7 @@ Concept of the replication border and corresponding db parameter `-soft_replicationborder_in_numrows` described here: -- [Best Practices](https://docs.exasol.com/db/latest/performance/best_practices.htm?Highlight=replication) +- [Best Practices](https://docs.exasol.com/db/latest/performance/best_practices.htm) - [Replication border in Exasol 6.1](https://exasol.my.site.com/s/article/Replication-border-in-Exasol-6-1) - [Replication border in Exasol 8](https://exasol.my.site.com/s/article/Changelog-content-16000) From ea36c6206a33b28ffd763f2b3fcdd8d330376150 Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Mon, 28 Apr 2025 13:44:20 +0200 Subject: [PATCH 5/8] Update Support-and-Services/subquery-replication-border.md Co-authored-by: allipatev <58830344+allipatev@users.noreply.github.com> --- Support-and-Services/subquery-replication-border.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Support-and-Services/subquery-replication-border.md b/Support-and-Services/subquery-replication-border.md index c09cf000..50eac42a 100644 --- a/Support-and-Services/subquery-replication-border.md +++ b/Support-and-Services/subquery-replication-border.md @@ -2,7 +2,7 @@ ## Background -Concept of the replication border and corresponding db parameter `-soft_replicationborder_in_numrows` described here: +Concept of the replication border and corresponding DB parameter `-soft_replicationborder_in_numrows` are described here: - [Best Practices](https://docs.exasol.com/db/latest/performance/best_practices.htm) - [Replication border in Exasol 6.1](https://exasol.my.site.com/s/article/Replication-border-in-Exasol-6-1) From 333741985c09e86418c605340c2574df1a4125d5 Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Mon, 28 Apr 2025 13:44:36 +0200 Subject: [PATCH 6/8] Update Support-and-Services/subquery-replication-border.md Co-authored-by: allipatev <58830344+allipatev@users.noreply.github.com> --- Support-and-Services/subquery-replication-border.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Support-and-Services/subquery-replication-border.md b/Support-and-Services/subquery-replication-border.md index 50eac42a..531cd17c 100644 --- a/Support-and-Services/subquery-replication-border.md +++ b/Support-and-Services/subquery-replication-border.md @@ -12,7 +12,7 @@ But `-soft_replicationborder_in_numrows` only works for persistent tables, for t However, there is another undocumented parameter `-subqueryreplicationborder` which plays exactly the same role but only for subquery's temp tables. - When the Optimizer decides if a subquery or materialized table should be replicated, it uses the subquery replication border parameter. It also defaults to 100000 and can be explicitly altered by using the command-line parameter `-subqueryreplicationborder`, same way as with the standard replication border. -- Increasing this parameter can lead to higher DBRAM usage, which may alter the system's behavior. In some cases, this can result in excessive memory consumption and overall system slowdown. Therefore, please adjust this setting with caution. +- Increasing this parameter can lead to higher DBRAM usage, which may affect the system's behavior. In some cases, this can result in excessive memory consumption and overall system slowdown. Therefore, please adjust this setting with caution. - IMPORTANT: This is an undocumented parameter, so we cannot guarantee that its behavior will remain unchanged in the future. However, it has been confirmed that there are no plans to modify this behavior in version 8. - In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM\SESSION command instead of db command-line parameter. But for the `-subqueryreplicationborder` the same is not provided. So the only way of changing it remains db command-line parameter. From 459d25189f144b853f37908b4180c82225c39f0b Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Fri, 2 May 2025 14:19:49 +0200 Subject: [PATCH 7/8] Update Support-and-Services/subquery-replication-border.md Co-authored-by: allipatev <58830344+allipatev@users.noreply.github.com> --- Support-and-Services/subquery-replication-border.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Support-and-Services/subquery-replication-border.md b/Support-and-Services/subquery-replication-border.md index 531cd17c..e4c3328a 100644 --- a/Support-and-Services/subquery-replication-border.md +++ b/Support-and-Services/subquery-replication-border.md @@ -14,7 +14,7 @@ However, there is another undocumented parameter `-subqueryreplicationborder` wh - When the Optimizer decides if a subquery or materialized table should be replicated, it uses the subquery replication border parameter. It also defaults to 100000 and can be explicitly altered by using the command-line parameter `-subqueryreplicationborder`, same way as with the standard replication border. - Increasing this parameter can lead to higher DBRAM usage, which may affect the system's behavior. In some cases, this can result in excessive memory consumption and overall system slowdown. Therefore, please adjust this setting with caution. - IMPORTANT: This is an undocumented parameter, so we cannot guarantee that its behavior will remain unchanged in the future. However, it has been confirmed that there are no plans to modify this behavior in version 8. -- In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM\SESSION command instead of db command-line parameter. But for the `-subqueryreplicationborder` the same is not provided. So the only way of changing it remains db command-line parameter. +- In v8 the proper way of changing `-soft_replicationborder_in_numrows` is ALTER SYSTEM command instead of DB parameter. But for the `-subqueryreplicationborder` the same is not provided. So the only way of changing it remains DB parameter. ## How to adjust SubqueryReplication border From f0beffb9f9bd0de4eb3ac6ae151a9a5dfd9ff0ce Mon Sep 17 00:00:00 2001 From: Vitalii Shilin Date: Fri, 2 May 2025 14:24:03 +0200 Subject: [PATCH 8/8] Rename subquery-replication-border.md to subquery-replication-border.md --- .../subquery-replication-border.md | 0 1 file changed, 0 insertions(+), 0 deletions(-) rename {Support-and-Services => Database-Features}/subquery-replication-border.md (100%) diff --git a/Support-and-Services/subquery-replication-border.md b/Database-Features/subquery-replication-border.md similarity index 100% rename from Support-and-Services/subquery-replication-border.md rename to Database-Features/subquery-replication-border.md