make a more recent snapshot of ldb available to interested

people. Note that I decided to make it LGPL.

ldb is not finished yet, but enough of it is there for people to get
an idea of what it does, and quite a few simple tests work
(This used to be commit dc6f41f9e777d37f883303ddef0d96840d80f78e)

1 files changed, 41 insertions, 0 deletions

diff --git a/source4/lib/ldb/docs/design.txt b/source4/lib/ldb/docs/design.txt
new file mode 100644
index 00000000000..0bb278b5b42
--- /dev/null
+++ b/source4/lib/ldb/docs/design.txt
@@ -0,0 +1,41 @@
+The list of indexed fields
+--------------------------
+
+dn=@INDEXLIST
+	list of field names that are indexed
+
+	contains fields of type @IDXATTR which contain attriute names
+	of indexed fields
+
+
+Data records
+------------
+
+for each user record in the db there is:
+    main record
+	 key: DN=dn
+	 data: packed attribute/value list
+
+    a index record for each indexed field in the record
+
+
+Index Records
+-------------
+
+The index records contain the list of dn's that contain records
+matching the index key
+
+All index records are of the form:
+      dn=@INDEX:field:value
+
+and contain fields of type @IDX which are the dns of the records
+that have that value for some attribute
+
+
+Search Expressions
+------------------
+
+Very similar to LDAP search expressions, but does not allow ~=, <= or >=
+
+	attrib0 := (field=value)
+	attrib := attrib0 | (attrib&&attrib) | (attrib||attrib) | !attrib