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Tom Lane
2bbe9112ae
\gexec executes the just-entered query, like \g, but instead of printing the results it takes each field as a SQL command to send to the server. Computing a series of queries to be executed is a fairly common thing, but up to now you always had to resort to kluges like writing the queries to a file and then inputting the file. Now it can be done with no intermediate step. The implementation is fairly straightforward except for its interaction with FETCH_COUNT. ExecQueryUsingCursor isn't capable of being called recursively, and even if it were, its need to create a transaction block interferes unpleasantly with the desired behavior of \gexec after a failure of a generated query (i.e., that it can continue). Therefore, disable use of ExecQueryUsingCursor when doing the master \gexec query. We can still apply it to individual generated queries, however, and there might be some value in doing so. While testing this feature's interaction with single-step mode, I (tgl) was led to conclude that SendQuery needs to recognize SIGINT (cancel_pressed) as a negative response to the single-step prompt. Perhaps that's a back-patchable bug fix, but for now I just included it here. Corey Huinker, reviewed by Jim Nasby, Daniel Vérité, and myself
<!-- doc/src/sgml/README.links -->
Linking within SGML documents can be confusing, so here is a summary:
Intra-document Linking
----------------------
<xref>
use to get chapter/section number from the title of the target
link, or xreflabel if defined at the target, or refentrytitle if target
is a refentry; has no close tag
http://www.oasis-open.org/docbook/documentation/reference/html/xref.html
<link>
use to supply text for the link, requires </link>
http://www.oasis-open.org/docbook/documentation/reference/html/link.html
linkend=
controls the target of the link/xref, required
endterm=
for <xref>, allows the text of the link/xref to be taken from a
different link target title
External Linking
----------------
<ulink>
like <link>, but uses a URL (not a document target); requires
</ulink>; if no text is specified, the URL appears as the link
text
http://www.oasis-open.org/docbook/documentation/reference/html/ulink.html
url=
used by <ulink> to specify the URL, required
Guidelines
----------
o If you want to supply text, use <link>, else <xref>
o Do not use text with <ulink> so the URL appears in printed output
o Specific nouns like GUC variables, SQL commands, and contrib modules
usually have xreflabels