Notes on using sqlite3

diff --git a/DATABASE b/DATABASE
index b498c2a0182b8ec8872892ccb4d3988369c10c39..a4bc2130b8d6ad8d0cdd777e8d5e229f506667c0 100644 (file)
--- a/DATABASE
+++ b/DATABASE
@@ -57,6 +57,14 @@ mysql:
 +---------------------+-------+
 6 rows in set (0.00 sec)
 
+2016-01-08:
+
+Hey, turns out my default sqlite verstion 2.8.17 cannot handle this,
+but sqlite 3 works like a charm.
+[#include test.sql]
+I may be replacing the backend. Requires different linux/dbstore.c
+and web/query.cgi rewritten to use HDBC.sqlite3.
+
 2015-12-20:
 
 After some playing with it, I think it is a mistake. One of my assumed

diff --git a/test.sql b/test.sql
new file mode 100644 (file)
index 0000000..f4e929e
--- /dev/null
+++ b/test.sql
@@ -0,0 +1,21 @@
+drop table if exists adjustment;
+drop table if exists counter;
+create table adjustment (timestamp datetime, value int);
+create table counter    (timestamp datetime, value int);
+
+insert into adjustment values ('2016-01-07 00:00:00', 10);
+insert into counter    values ('2016-01-07 00:00:01', 5);
+insert into counter    values ('2016-01-07 00:00:02', 10);
+insert into counter    values ('2016-01-07 00:00:03', 15);
+insert into adjustment values ('2016-01-07 00:00:04', 30);
+insert into counter    values ('2016-01-07 00:00:05', 0);
+insert into counter    values ('2016-01-07 00:00:06', 5);
+insert into counter    values ('2016-01-07 00:00:07', 10);
+
+select timestamp, value+adj as value from
+  (select c.timestamp timestamp, c.value value, 
+                (select value from adjustment a
+                        where a.timestamp <= c.timestamp
+                        order by timestamp desc limit 1) adj from counter c
+  ) t;
+