postgres.git / summary / log / commit / refs
commit 2e7390928e80fe1e7bfd581724f7dcce3d27197d
Author: Tom Lane <tgl@sss.pgh.pa.us>
Date: Tue Jul 15 20:35:42 2025 +0000
First released in: 13.22, 14.19, 15.14, 16.10, 17.6, 18.0
Doc: clarify description of current-date/time functions.
Minor wordsmithing of the func.sgml paragraph describing
statement_timestamp() and allied functions: don't switch between
"statement" and "command" when those are being used to mean about
the same thing.
Also, add some text to protocol.sgml describing the perhaps-surprising
behavior these functions have in a multi-statement Query message.
Reported-by: P M <petermittere@gmail.com>
Author: Tom Lane <tgl@sss.pgh.pa.us>
Reviewed-by: Laurenz Albe <laurenz.albe@cybertec.at>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/175223006802.3157505.14764328206246105568@wrigleys.postgresql.org
Backpatch-through: 13
doc/src/sgml/func.sgml | 6 +++---
doc/src/sgml/protocol.sgml | 10 ++++++++++
2 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/doc/src/sgml/func.sgml b/doc/src/sgml/func.sgml
index f4d6d69630e..4faa7782dce 100644
--- a/doc/src/sgml/func.sgml
+++ b/doc/src/sgml/func.sgml
@@ -10802,10 +10802,10 @@ now()
statement (more specifically, the time of receipt of the latest command
message from the client).
<function>statement_timestamp()</function> and <function>transaction_timestamp()</function>
- return the same value during the first command of a transaction, but might
- differ during subsequent commands.
+ return the same value during the first statement of a transaction, but might
+ differ during subsequent statements.
<function>clock_timestamp()</function> returns the actual current time, and
- therefore its value changes even within a single SQL command.
+ therefore its value changes even within a single SQL statement.
<function>timeofday()</function> is a historical
<productname>PostgreSQL</productname> function. Like
<function>clock_timestamp()</function>, it returns the actual current time,
diff --git a/doc/src/sgml/protocol.sgml b/doc/src/sgml/protocol.sgml
index 14203572ea7..c3df074bc3a 100644
--- a/doc/src/sgml/protocol.sgml
+++ b/doc/src/sgml/protocol.sgml
@@ -800,6 +800,16 @@ SELCT 1/0;<!-- this typo is intentional -->
Errors detected at semantic analysis or later, such as a misspelled
table or column name, do not have this effect.
</para>
+
+ <para>
+ Lastly, note that all the statements within the Query message will
+ observe the same value of <function>statement_timestamp()</function>,
+ since that timestamp is updated only upon receipt of the Query
+ message. This will result in them all observing the same
+ value of <function>transaction_timestamp()</function> as well,
+ except in cases where the query string ends a previously-started
+ transaction and begins a new one.
+ </para>
</sect3>
</sect2>
[parent: 53a936b61f12]