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Posted to derby-dev@db.apache.org by "Mike Matrigali (JIRA)" <ji...@apache.org> on 2012/06/05 23:29:23 UTC
[jira] [Created] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Mike Matrigali created DERBY-5799:
-------------------------------------
Summary: add more info on when Derby chooses 32k page size for tables.
Key: DERBY-5799
URL: https://issues.apache.org/jira/browse/DERBY-5799
Project: Derby
Issue Type: Improvement
Components: Documentation
Affects Versions: 10.8.2.2
Reporter: Mike Matrigali
Priority: Minor
Enhance the following documentation to explain all cases when Derby will default a table to 32k.
current doc:
http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
1) better describe what "long" means. Originally this was clear as it meant just datatypes with
the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
all the types, or just something like long, Blob and/or Clob.
2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
variable length data like varchar can't be known at create time, ...
I don't think we should try to document exact derby algorithm, rather doc that Derby will default
to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
do think it is useful to doc that Derby will include both existence of long columns and the estimate
length of the row.
Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
/**
* The default page size to use for tables that contain a long column.
**/
public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
/**
* The bump threshold for pages sizes for create tables
* If the approximate column sizes of a table is greater than this
* threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
* provided the page size is not already specified as a property
**/
public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
/**
* The bump threshold for pages size for index.
* If the approximate key columns of an index is greater than this
* threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
G
* provided the page size is not already specified as a property
**/
public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Commented] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Knut Anders Hatlen (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13471425#comment-13471425 ]
Knut Anders Hatlen commented on DERBY-5799:
-------------------------------------------
Hi Kim,
Your changes look right to me. +1
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2, 10.9.1.0
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
> Attachments: DERBY-5799.diff, rrefproper40688.html
>
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Updated] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kim Haase updated DERBY-5799:
-----------------------------
Issue & fix info: Patch Available
Affects Version/s: 10.9.1.0
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2, 10.9.1.0
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
> Attachments: DERBY-5799.diff, rrefproper40688.html
>
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Resolved] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kim Haase resolved DERBY-5799.
------------------------------
Resolution: Fixed
Fix Version/s: 10.10.0.0
10.9.1.1
10.8.2.3
Issue & fix info: (was: Patch Available)
Thanks very much, Knut.
Committed patch DERBY-5799.diff to documentation trunk at revision 1395558.
Merged to 10.9 doc branch at revision 1395566.
Merged to 10.8 doc branch at revision 1395570.
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2, 10.9.1.0
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
> Fix For: 10.8.2.3, 10.9.1.1, 10.10.0.0
>
> Attachments: DERBY-5799.diff, rrefproper40688.html
>
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Updated] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kim Haase updated DERBY-5799:
-----------------------------
Attachment: rrefproper40688.html
DERBY-5799.diff
Based on my hypothesis, I'm attaching DERBY-5799.diff and rrefproper40688.html. Please let me know if changes are needed. Thanks!
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2, 10.9.1.0
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
> Attachments: DERBY-5799.diff, rrefproper40688.html
>
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Closed] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kim Haase closed DERBY-5799.
----------------------------
Closing, since change has appeared in Latest Alpha Manuals.
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2, 10.9.1.0
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
> Fix For: 10.8.2.3, 10.9.1.1, 10.10.0.0
>
> Attachments: DERBY-5799.diff, rrefproper40688.html
>
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Assigned] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Kim Haase reassigned DERBY-5799:
--------------------------------
Assignee: Kim Haase
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Commented] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13470365#comment-13470365 ]
Kim Haase commented on DERBY-5799:
----------------------------------
Having received no comments, I'm planning to commit this patch on October 8. I hope I guessed right about the data types.
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2, 10.9.1.0
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
> Attachments: DERBY-5799.diff, rrefproper40688.html
>
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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[jira] [Commented] (DERBY-5799) add more info on when Derby chooses
32k page size for tables.
Posted by "Kim Haase (JIRA)" <ji...@apache.org>.
[ https://issues.apache.org/jira/browse/DERBY-5799?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13458769#comment-13458769 ]
Kim Haase commented on DERBY-5799:
----------------------------------
I'm finally working on this -- thanks for the info, Mike.
Probably a naive question: for column size, what does "long" mean in terms of data types? Does it refer to LONG VARCHAR and LONG VARCHAR FOR BIT DATA? I don't think it means BIGINT (java.lang.Long) because that's only 8 bytes.
I'm figuring I might as well be precise. Thanks!
> add more info on when Derby chooses 32k page size for tables.
> -------------------------------------------------------------
>
> Key: DERBY-5799
> URL: https://issues.apache.org/jira/browse/DERBY-5799
> Project: Derby
> Issue Type: Improvement
> Components: Documentation
> Affects Versions: 10.8.2.2
> Reporter: Mike Matrigali
> Assignee: Kim Haase
> Priority: Minor
>
> Enhance the following documentation to explain all cases when Derby will default a table to 32k.
> current doc:
> http://db.apache.org/derby/docs/10.8/ref/rrefproper40688.html
> 1) better describe what "long" means. Originally this was clear as it meant just datatypes with
> the "long" qualifier. Now it also includes Blob and Clob columns. Not sure if we should list
> all the types, or just something like long, Blob and/or Clob.
> 2) Derby will also choose 32k if the approximate length of the columns declared at create time is greater than 4k. Approximate is used as each different datatype may or may not be fixed length
> when stored on the page. Character data may take 1, 2, or 3 bytes per character, obviously
> variable length data like varchar can't be known at create time, ...
> I don't think we should try to document exact derby algorithm, rather doc that Derby will default
> to what it thinks should be the best size of either 4k or 32k unless user chooses to override. I
> do think it is useful to doc that Derby will include both existence of long columns and the estimate
> length of the row.
> Here some comments from Property.java that describes constants used, if these constants every change then documentation would change also:
> /**
> * The default page size to use for tables that contain a long column.
> **/
> public static final String PAGE_SIZE_DEFAULT_LONG = "32768";
> /**
> * The bump threshold for pages sizes for create tables
> * If the approximate column sizes of a table is greater than this
> * threshold, the page size for the tbl is bumped to PAGE_SIZE_DEFAULT_LONG
> * provided the page size is not already specified as a property
> **/
> public static final int TBL_PAGE_SIZE_BUMP_THRESHOLD = 4096;
> /**
> * The bump threshold for pages size for index.
> * If the approximate key columns of an index is greater than this
> * threshold, the page size for the index is bumped to PAGE_SIZE_DEFAULT_LON
> G
> * provided the page size is not already specified as a property
> **/
> public static final int IDX_PAGE_SIZE_BUMP_THRESHOLD = 1024;
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