Glyn Astill wrote:
Hi people,
I've tried posting on the general list about this, but I never get
a
reply, so I'm trying here.
I think you'll probably have more luck with a TCL list than the PG
hackers list. However, I've attached some pltcl functions I put together
ages ago to do this sort of thing. Hopefully that will help you.
--
Richard Huxton
Archonet Ltd
-- History Tracking Trigger-Functions
--
BEGIN;
-- tcl_track_history(TABLE-NAME)
-- Set TABLE-NAME when creating the trigger. Will automatically record change
-- details in tables history/history_detail
--
CREATE OR REPLACE FUNCTION tcl_track_history() RETURNS trigger AS '
switch $TG_op {
DELETE {
if { [llength [array names OLD cid]] > 0 } {
set clival $OLD(cid)
} else {
set clival "NULL"
}
spi_exec "INSERT INTO history (cid,tbl,act) VALUES ($clival, \'$1\', \'D\')"
}
INSERT {
if { [llength [array names NEW cid]] > 0 } {
set clival $NEW(cid)
} else {
set clival "NULL"
}
spi_exec "INSERT INTO history (cid,tbl,act) VALUES ($clival, \'$1\', \'I\')"
}
UPDATE {
if { [llength [array names OLD cid]] > 0 } {
set clival $OLD(cid)
} else {
set clival "NULL"
}
set inserted_main_history_row false
foreach {col} $TG_relatts {
# First result seems to be an empty string when stepping through columns
if { $col > "" } {
# Check if OLD/NEW contain a value
if { [llength [array names OLD $col]] > 0 } {
set oldval $OLD($col)
} else {
set oldval "NULL"
}
if { [llength [array names NEW $col]] > 0 } {
set newval $NEW($col)
} else {
set newval "NULL"
}
if { $oldval != $newval } {
if { !$inserted_main_history_row } {
spi_exec "INSERT INTO history (cid,tbl,act) VALUES ($clival, \'$1\', \'U\')"
set inserted_main_history_row true
}
spi_exec "INSERT INTO history_detail (col,was) VALUES (\'$col\', \'[ quote $oldval ]\')"
}
}
}
}
}
return OK
' LANGUAGE pltcl;
CREATE TRIGGER history_trig AFTER INSERT OR UPDATE OR DELETE ON client FOR EACH ROW EXECUTE PROCEDURE tcl_track_history('client');
CREATE TRIGGER history_trig AFTER INSERT OR UPDATE OR DELETE ON client_keyworkers FOR EACH ROW EXECUTE PROCEDURE tcl_track_history('client_keyworkers');
CREATE TRIGGER history_trig AFTER INSERT OR UPDATE OR DELETE ON client_notes FOR EACH ROW EXECUTE PROCEDURE tcl_track_history('client_notes');
COMMIT;
BEGIN;
CREATE OR REPLACE FUNCTION tcl_track_answers() RETURNS trigger AS '
switch $TG_op {
DELETE {
if { [llength [array names OLD cid]] > 0 } {
set clival $OLD(cid)
} else {
set clival "NULL"
}
spi_exec "INSERT INTO history (cid,tbl,act) VALUES ($clival, \'$1\', \'D\')"
}
INSERT {
if { [llength [array names NEW cid]] > 0 } {
set clival $NEW(cid)
} else {
set clival "NULL"
}
spi_exec "INSERT INTO history (cid,tbl,act) VALUES ($clival, \'$1\', \'I\')"
}
UPDATE {
# Get question title into var $qn_title
spi_exec "SELECT \'Q\' || qid || \' - \' || title AS qn_title FROM question WHERE qid = $OLD(qid)"
if { [llength [array names OLD cid]] > 0 } {
set clival $OLD(cid)
} else {
set clival "NULL"
}
# Check if OLD/NEW contain a value
if { [llength [array names OLD text_val]] > 0 } {
set oldval $OLD(text_val)
} else {
set oldval "NULL"
}
if { [llength [array names NEW text_val]] > 0 } {
set newval $NEW(text_val)
} else {
set newval "NULL"
}
if { $oldval != $newval } {
spi_exec "INSERT INTO history (cid,tbl,act) VALUES ($clival, \'$1\', \'U\')"
spi_exec "INSERT INTO history_detail (col,was) VALUES (\'$qn_title\', \'[ quote $oldval ]\')"
}
}
}
return OK
' LANGUAGE pltcl;
CREATE TRIGGER history_trig AFTER INSERT OR UPDATE OR DELETE ON client_answer FOR EACH ROW EXECUTE PROCEDURE tcl_track_answers('client_answer');
UPDATE client_answer SET text_val = 'partially sighted',ts=now() WHERE aid=20;
COMMIT;
---------------------------(end of broadcast)---------------------------
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