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Comment:Update the file format document to indicate that the number of rows in an index in sqlite_stat1 can be less than the number of table rows in the case of a partial index.
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SHA1: 42f14ae85f51a5068daefef0a10760d2a16d3490
User & Date: drh 2016-01-26 15:04:33
Context
2016-02-02
02:05
Enhance the comment on the sqlite3_index_constraint.iColumn field to help bring attention to the fact that it can be negative for a rowid column. check-in: be35c1ae8e user: drh tags: trunk
2016-01-26
15:04
Update the file format document to indicate that the number of rows in an index in sqlite_stat1 can be less than the number of table rows in the case of a partial index. check-in: 42f14ae85f user: drh tags: trunk
2016-01-25
13:55
Merge 3.10.2 changes. Add the SQLITE_EXTRA_DURABLE=1 compile-time option. check-in: d39c6c7cfc user: drh tags: trunk
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Changes to pages/fileformat2.in.

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<p> ^(There is normally one row per index, with the index identified by the
name in the sqlite_stat1.idx column.)^  ^(The sqlite_stat1.tbl column is
the name of the table to which the index belongs.)^  ^(In each such row, 
the sqlite_stat.stat column will be
a string consisting of a list of integers followed by zero or more 
arguments.)^  ^The first integer in this
list is the approximate number of rows in the index and in the table.


^The second integer is the approximate average number of rows in the index
that have the same value in the first column of the index.  ^The third 
integer is the approximate average number of rows in the index that have 
the same value for the first two columns.  ^The N-th integer (for N>1) 
is the approximate average number of rows in 
the index which have the same value for the first N-1 columns.  ^For
a K-column index, there will be K+1 integers in the stat column.  ^If







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<p> ^(There is normally one row per index, with the index identified by the
name in the sqlite_stat1.idx column.)^  ^(The sqlite_stat1.tbl column is
the name of the table to which the index belongs.)^  ^(In each such row, 
the sqlite_stat.stat column will be
a string consisting of a list of integers followed by zero or more 
arguments.)^  ^The first integer in this
list is the approximate number of rows in the index.  (The number of
rows in the index is the same as the number of rows in the table,
except for [partial indexes].)
^The second integer is the approximate average number of rows in the index
that have the same value in the first column of the index.  ^The third 
integer is the approximate average number of rows in the index that have 
the same value for the first two columns.  ^The N-th integer (for N>1) 
is the approximate average number of rows in 
the index which have the same value for the first N-1 columns.  ^For
a K-column index, there will be K+1 integers in the stat column.  ^If