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Updated NULL column & fixed/var column info in HACKERS file

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brianb 2000-03-19 03:03:50 +00:00
parent ae39081ebd
commit 61cf29ad4f
1 changed files with 6 additions and 3 deletions
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9
HACKERS
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@ -134,10 +134,12 @@ one for each column present. It's format is as follows:
+------+---------+--------------------------------------------------------+
| ???? | 1 byte | Column Type (see table below) |
| ???? | 2 bytes | Column Number, ascending sequential number, starts at 0|
| ???? | 1 byte | appears to denote whether a text field is required |
| ???? | 1 byte | unknown. 1 is sometimes seen in text types |
| ???? | 1 byte | unknown |
| ???? | 4 bytes | Column Number (again) |
| ???? | 7 bytes | ??? (timestamp?) |
| ???? | 6 bytes | ??? (timestamp?) |
| ???? | 1 bytes | bitmask of some sort. low order bit indicates variable |
| | | length column |
| ???? | 2 bytes | length of column |
+-------------------------------------------------------------------------+
@ -179,7 +181,8 @@ Each data row looks like this:
| ???? | 1 byte | length of data from beginning of record |
| ???? | n bytes | offset from start of row for each variable length col |
| ???? | 1 byte | number of variable length columns |
| ???? | 1 byte | Unknown |
| ???? | n bytes | Null indicator. size is 1 byte per 8 columns. |
| | | 0 indicates a null value. |
+------+---------+--------------------------------------------------------+
Note: it is possible for the offset to the beginning of a variable length