diff --git a/paper/db-summary.pic b/paper/db-summary.pic
new file mode 100644
index 0000000..48f26a3
--- /dev/null
+++ b/paper/db-summary.pic
@@ -0,0 +1,54 @@
+.PS
+colheight = -1.5
+colwidth = 2.0
+
+.gcolor white
+COL0: line from Here to Here + (0,colheight)
+.gcolor
+COL1: line same from COL0 + (0.9, 0)
+COL2: line same from COL1 + (colwidth, 0)
+COL3: line same from COL2 + (colwidth, 0)
+COL4: line same from COL3 + (colwidth, 0)
+
+txtdist = -0.1
+row1 = -0.2
+rowdist = -0.4
+
+.ps +2
+RAMONLY:  "RAM-only" rjust at COL1 + (txtdist, row1)
+CACHE:    "Cache"    rjust at RAMONLY + (0, rowdist)
+box wid 7.2 with .w at CACHE + (-0.9, rowdist) shaded "green"
+COMMON:   "Common"   rjust at CACHE   + (0, rowdist)
+UNCACHED: "Uncached" rjust at COMMON  + (0, rowdist)
+.ps
+
+.ps +4
+SPEED:       "Speed"       at 1/2 between COL1 and COL2 + (0, 0.5)
+MEMORY:      "Memory use"  at 1/2 between COL2 and COL3 + (0, 0.5)
+PERSISTANCE: "Persistance" at 1/2 between COL3 and COL4 + (0, 0.5)
+.ps
+
+.ps +2
+"Ultra fast" at (SPEED,RAMONLY)
+.gcolor red
+"Entire data-set" at (MEMORY,RAMONLY)
+"No" at (PERSISTANCE,RAMONLY)
+.gcolor
+
+"Ultra fast" at (SPEED,CACHE)
+.gcolor red
+"Entire data-set" at (MEMORY,CACHE)
+.gcolor
+"Yes" at (PERSISTANCE,CACHE)
+
+"Fast most of the time" at (SPEED,COMMON)
+"Configurable" at (MEMORY,COMMON)
+"Yes" at (PERSISTANCE,COMMON)
+
+.gcolor red
+"Slow" at (SPEED,UNCACHED)
+.gcolor
+"Almost none" at (MEMORY,UNCACHED)
+"Yes" at (PERSISTANCE,UNCACHED)
+.ps
+.PE
diff --git a/paper/paper.ms b/paper/paper.ms
index 524c780..fc7acae 100644
--- a/paper/paper.ms
+++ b/paper/paper.ms
@@ -266,9 +266,9 @@ This is a simple object
 with a name, a color and a list of associated keywords (fast, elegant, etc.).
 .SOURCE Ruby ps=9 vs=10
 class Car
-	property name     : String        # ex: Corvet
-	property color    : String        # ex: red
-	property keywords : Array(String) # ex: [fast, impressive]
+	property name     : String        # e.g. Corvet
+	property color    : String        # e.g. red
+	property keywords : Array(String) # e.g. [fast, impressive]
 end
 .SOURCE
 .
@@ -965,7 +965,18 @@ The duration of the request would then be the addition of both tag requests and
 .
 .
 .SS Summary of the different databases and their use
-.LP
+The following table shows the differences between the database implementations in DODB.
+.so db-summary.pic
+.QP
+To put things into perspective, request duration is 120 ns for RAM-only and Cache databases and
+200 ns for Common database (a 67 % slow down, but still impressive) when on a cache hit (22 µs otherwise, such as uncached database),
+uncached database is 170 to 180 times slower than RAM-only (22 µs vs 120 ns) which still could be acceptable but Common database should be considered instead.
+
+Both RAM-only and Cache databases require to keep the entire database in-memory.
+The Common database can be tailored to any particular situation as long as a LRU eviction policy is relevant.
+Uncached database doesn't keep anything in-memory.
+.QE
+
 .B "RAM-only database"
 is the fastest database but dedicated to short-lived data (data is not saved on disk).