Result File Contents

Any errors detected in the databank file are written to the result file directly after the identification record for the table affected.

The result file begins with the following information:

Databank file name.
Time when the DBC operation was performed.
Version of Mimer SQL under which the databank was created (if this is not the same as the current version there will also be a `converted to' message).
A backup timestamp.
Structure level.
System identifier for the databank.
Databank sequence number (0 = master databank, >0 = a shadow).
Check flag.
Number of bitmap pages (starting at 0).
Root pages (starting at 1).
Number of pages allocated.
Number of pages used.

If the check flag indicates that the databank was not properly closed when Mimer SQL is stopped, there may be an additional message saying:

     * No bitmap checking against databank!

DBC B*-tree Table Information

An identification record is given for each table in the databank. The following information is shown:


Information	Description
Tabid	The system identification number of the table. This is the number used to identify the table in the data dictionary. The table name is not stored directly in the databank file.
Startp	The page number of the start page for the highest index level. If the number of levels is 1, this is the only data page. If the start page is 0, the table is empty.
Levels	The number of levels in the table storage structure.
Keylen	The length of the primary key in bytes.
Reclen	The record length (row length) of the table.
Type of table	Any of the following values: `Base table Secondary index table Collation description table LOB directory table`.
Type of compression	Any of the following values: `Mimer LZM compression Mimer LZU compression Mimer RLE compression`none.
Collation version	Displayed if any key part of the table is using collation.
Status of table	`Resident` or `Marked for delete`.
Index page size	Size of the index page in bytes.
Data page size	Size of the data page in bytes.
Number of index pages	Indicates how many index pages were checked.
Number of data pages	Indicates how many data pages were checked.
Required/Allocated datapages	Gives an approximate measure of the space used in the data pages. This is expressed as a percentage, which may be >100% for data pages having variable-length (i.e. compressed) records because the required number of pages is calculated based on uncompressed record sizes.
Reached no of records	If no errors are reported, the number of records reached is equal to the total number of records (rows) stored for the table.

DBC Sequential Table Information

The following information is shown:


Information	Description
Tabid	Ordered identification.
Startpage	First page in the sequential file.
Endpage	Last page in the sequential file.
Type of table	Any of the following values: `Sequential table Collation description table LOB directory table`.
Type of compression	Any of the following values: `Mimer LZM compression Mimer LZU compression Mimer RLE compression`none.
Status of table	`Resident` or `Marked for delete`.
Index Page size	Size of the index page in bytes.
Data Page size	Size of the data page in bytes.
No. of index pages read	Number of index pages checked.
No. of data pages read	Number of data pages checked.
No. of records read	Number of records checked.

DBC LOGDB Backup Information

The following information is shown:


Information	Description
Timestamp page	Describes actual timestamps for databanks included in the log.

Error Messages

The following error situations are described by explicit messages in the result file:

Bitmap Errors


Error message	Explanation
* Illegal number of free bits in bitmap	The number of free bits in the bitmap is marked as a negative number or as a number greater than the permissible value.
* Illegal pointer to first word with free bit in bitmap	The pointer to the first word is either negative or greater than the number of words per page, or points outside the number of allocated pages.

Root Page Errors


Error message	Explanation
* Illegal record length in root page	The record length is not valid for the current version or for the site.
* Pageno. outside databank: x * Pageno. not marked as used: x	The reference to the page number (`x`) is invalid. (Applies only where there is more than one root page.)

Sequential Structure Errors


Error message	Explanation
* Pointer to previous page invalid	Error in page linkage.
* Invalid record length	The record length is either not the same as in the previous page or outside the page limits.
* Record crosses page boundary	A record stretches over the page limits.

Table Structure Errors


Error message	Explanation
* Error in root record	The value for start page, levels, key length or record length is outside the legal values for the site.
* Page has illegal record length: x	The record length (`x`) given in the page is not the same as that given for the table.
* Page has illegal last-record pointer: x	The pointer (`x`) to data within a page is outside the page limits. The limits are the values of bytes/header and bytes/page.
* Page has records in wrong order. Pos: x	The records in the page are not correctly sorted. The value of x is the byte position within the page for the start of the wrong record.
* Page has last-record key > index key. Pos: x	The records within a page include key values greater than those in the index level above. The value of x is the byte position within the page for the start of the last record.
* Page no. outside databank: x	Reference is made to a page number (x) which is higher than the highest allocated page.
* Page no. referenced twice	There are at least two references to the same page number (x). One of these references should also give another error, or an error should have been notified earlier in the file.
* Page no. not marked as used: x Bitmap pageno: Word: Bit:	A page that is used is illegally marked as free. Continued insertion of data in the databank will result in a double referenced page.

All table structure errors are followed by a listing of the page numbers passed in the B*-tree structure on the way to the error. In the example below a y-value indicates the byte position in the page (corresponding x-value) where the record holding the reference to the next level starts:

 B*-tree
 Page no:    x1   x2   x3  ....  xn
 Byte pos:   y1   y2   y3  ....  yn

If the error occurs at an index level, the following additional message is given, and no checks are made at lower levels:

 Branch is interrupted