Re: MERGE and parsing with prepared statements

On Fri, Jul 15, 2022 at 03:43:41PM -0500, Justin Pryzby wrote:
> Should that sentence be removed from MERGE ?

Also, I think these examples should be more similar.

doc/src/sgml/ref/merge.sgml

> <programlisting>
> MERGE INTO CustomerAccount CA
> USING RecentTransactions T
> ON T.CustomerId = CA.CustomerId
> WHEN MATCHED THEN
> UPDATE SET Balance = Balance + TransactionValue
> WHEN NOT MATCHED THEN
> INSERT (CustomerId, Balance)
> VALUES (T.CustomerId, T.TransactionValue);
> </programlisting>
> </para>
>
> <para>
> Notice that this would be exactly equivalent to the following
> statement because the <literal>MATCHED</literal> result does not change
> during execution.
>
> <programlisting>
> MERGE INTO CustomerAccount CA
> USING (Select CustomerId, TransactionValue From RecentTransactions) AS T
> ON CA.CustomerId = T.CustomerId
> WHEN NOT MATCHED THEN
> INSERT (CustomerId, Balance)
> VALUES (T.CustomerId, T.TransactionValue)
> WHEN MATCHED THEN
> UPDATE SET Balance = Balance + TransactionValue;
> </programlisting>
> </para>

The "ON" lines can be the same.
The "MATCHED" can be in the same order.

--
Justin