# \#caqti **URL:** https://discuss.ocaml.org/tag/caqti/346.md [Latest](https://discuss.ocaml.org/latest.md) · [Categories](https://discuss.ocaml.org/categories.md) · [Tags](https://discuss.ocaml.org/tags.md) --- ## [Couldn't make \`ppx\_rapper\` work with \`dream\`](https://discuss.ocaml.org/t/couldnt-make-ppx-rapper-work-with-dream/16839)
**Author:** [@blurrcat](https://discuss.ocaml.org/u/blurrcat)\ **Replies:** 3\ **Last updated:** [June 23, 2025, 12:19am UTC](https://discuss.ocaml.org/t/couldnt-make-ppx-rapper-work-with-dream/16839 "2025-06-23T00:19:50Z")
Hello friends, I’m new to OCaml and I’d like to do a toy project with dream and ppx\_rapper. It seems the latest version of dream(1.0.0~alpha8) is not compatible with ppx\_rapper(details at the end of the post). I see a f… --- ## [Is there a way to use parameter with "WHERE LIKE %%" clause in Caqti's query template? \[Solved\]](https://discuss.ocaml.org/t/is-there-a-way-to-use-parameter-with-where-like-clause-in-caqtis-query-template-solved/14235)
**Author:** [@pyx](https://discuss.ocaml.org/u/pyx)\ **Replies:** 11\ **Last updated:** [March 2, 2024, 5:33pm UTC](https://discuss.ocaml.org/t/is-there-a-way-to-use-parameter-with-where-like-clause-in-caqtis-query-template-solved/14235 "2024-03-02T17:33:48Z")
I am trying to write something like: Caqti\_type.Std.(string -\>\* t2 int string) "SELECT id, content from post WHERE content LIKE %?%" and I got this exception “‘%’ is not allowed after parameter reference ‘?’”, which is… --- ## [Upcoming Caqti Release - TLS, Packaging, and minor breakage](https://discuss.ocaml.org/t/upcoming-caqti-release-tls-packaging-and-minor-breakage/13926)
**Author:** [@paurkedal](https://discuss.ocaml.org/u/paurkedal)\ **Replies:** 6\ **Last updated:** [February 20, 2024, 6:10pm UTC](https://discuss.ocaml.org/t/upcoming-caqti-release-tls-packaging-and-minor-breakage/13926 "2024-02-20T18:10:01Z")
The next Caqti release is almost ready if I proceed as planned, though I would like to lift plans in advance in case anyone has feedback. While Caqti 2 brought support for MirageOS (using PGX), it is missing TLS, which … --- ## [Running transactions in caqti with Dream and Rapper?](https://discuss.ocaml.org/t/running-transactions-in-caqti-with-dream-and-rapper/14053)
**Author:** [@MarcCoquand](https://discuss.ocaml.org/u/MarcCoquand)\ **Replies:** 4\ **Last updated:** [February 11, 2024, 8:01pm UTC](https://discuss.ocaml.org/t/running-transactions-in-caqti-with-dream-and-rapper/14053 "2024-02-11T20:01:28Z")
Heya! I’m trying to figure out how to run transactions in Dream with Caqti sql. Say I have a few insert queries made with rapper let insert\_user id = \[%rapper get\_one {sql| INSERT INTO.... |sql}\] let insert-post id =… --- ## [Ppx\_rapper WHERE IN empty list](https://discuss.ocaml.org/t/ppx-rapper-where-in-empty-list/13669)
**Author:** [@mudrz](https://discuss.ocaml.org/u/mudrz)\ **Replies:** 9\ **Last updated:** [December 26, 2023, 3:02pm UTC](https://discuss.ocaml.org/t/ppx-rapper-where-in-empty-list/13669 "2023-12-26T15:02:08Z")
I have the following table: CREATE TABLE my\_table ( id integer GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY, label text ); INSERT INTO public.my\_table(id, label) VALUES (1,'item 1'), (2,'item 2'), (3,'item 3');… --- ## [What could hinder sql query statement from being invoked?](https://discuss.ocaml.org/t/what-could-hinder-sql-query-statement-from-being-invoked/12905)
**Author:** [@lubegasimon](https://discuss.ocaml.org/u/lubegasimon)\ **Replies:** 3\ **Last updated:** [August 27, 2023, 3:12pm UTC](https://discuss.ocaml.org/t/what-could-hinder-sql-query-statement-from-being-invoked/12905 "2023-08-27T15:12:37Z")
I am trying to get execute sql query statement but seems not to be a success. What could I be doing wrong? I have the following modules and the main is executed via dune exec ...main.exe (\* ./drop\_tbl.ml \*) open Caqti… --- ## [Trying to get Cacti example working](https://discuss.ocaml.org/t/trying-to-get-cacti-example-working/11790)
**Author:** [@garyrob](https://discuss.ocaml.org/u/garyrob)\ **Replies:** 9\ **Last updated:** [April 4, 2023, 8:15pm UTC](https://discuss.ocaml.org/t/trying-to-get-cacti-example-working/11790 "2023-04-04T20:15:29Z")
I am extremely frustrated and hoping someone can help me. I am trying to get the example code in the Caqti github working working. It’s for a project they call bikereg. Here are the steps I take: dune init proj bikereg… --- ## [Ppx\_rapper - join 2 tables and return a list](https://discuss.ocaml.org/t/ppx-rapper-join-2-tables-and-return-a-list/11277)
**Author:** [@mudrz](https://discuss.ocaml.org/u/mudrz)\ **Replies:** 3\ **Last updated:** [February 1, 2023, 4:28pm UTC](https://discuss.ocaml.org/t/ppx-rapper-join-2-tables-and-return-a-list/11277 "2023-02-01T16:28:13Z")
Hello, I’m trying to do something trivial - write a select query that joins 2 tables and returns a list of the results But I can’t come up with a query with the appropriate syntax, does anyone have experience with ppx\_… --- ## [Too many connections with Dream and mysql](https://discuss.ocaml.org/t/too-many-connections-with-dream-and-mysql/11224)
**Author:** [@Frederic\_Loyer](https://discuss.ocaml.org/u/Frederic_Loyer)\ **Replies:** 13\ **Last updated:** [January 25, 2023, 9:20am UTC](https://discuss.ocaml.org/t/too-many-connections-with-dream-and-mysql/11224 "2023-01-25T09:20:46Z")
I have the following errors multiple times : 22.01.23 17:25:58.628 dream.log WARN REQ 156 Aborted by: Failed to connect to \: Error 1040, Too many connections. 22.01.23 17:25:5… --- ## [\[ANN\] Caqti 1.9.0 and Plans for 2.0.0](https://discuss.ocaml.org/t/ann-caqti-1-9-0-and-plans-for-2-0-0/10448)
**Author:** [@paurkedal](https://discuss.ocaml.org/u/paurkedal)\ **Replies:** 4\ **Last updated:** [September 14, 2022, 1:46pm UTC](https://discuss.ocaml.org/t/ann-caqti-1-9-0-and-plans-for-2-0-0/10448 "2022-09-14T13:46:20Z")
First I would like to announce the 1.9.0 minor release, see the release notes below for details. Caqti is an interface to multiple database client libraries, covering MariaDB, PostgreSQL, and Sqlite3. There is also ongo… --- ## [\[ANN\] Caqti 1.8.0 and related news](https://discuss.ocaml.org/t/ann-caqti-1-8-0-and-related-news/9561)
**Author:** [@paurkedal](https://discuss.ocaml.org/u/paurkedal)\ **Replies:** 5\ **Last updated:** [March 27, 2022, 8:14pm UTC](https://discuss.ocaml.org/t/ann-caqti-1-8-0-and-related-news/9561 "2022-03-27T20:14:30Z")
I am happy to announce the second release of Caqti this year. The reason for the quick succession is partly an adjustment to the new API for request construction and partly that matchable error conditions did not make it… --- ## [\[ANN\] Caqti 1.7.0](https://discuss.ocaml.org/t/ann-caqti-1-7-0/9326)
**Author:** [@paurkedal](https://discuss.ocaml.org/u/paurkedal)\ **Replies:** 0\ **Last updated:** [February 14, 2022, 7:51am UTC](https://discuss.ocaml.org/t/ann-caqti-1-7-0/9326 "2022-02-14T07:51:18Z")
I am pleased to announce the release of Caqti 1.7.0. Caqti is a generic RDBMS client interface supporting MariaDB, PostgreSQL, and Sqlite3 via the corresponding bindings to the client libraries. The full release notes … --- ## [Caqti transaction examples](https://discuss.ocaml.org/t/caqti-transaction-examples/8220)
**Author:** [@mudrz](https://discuss.ocaml.org/u/mudrz)\ **Replies:** 0\ **Last updated:** [July 31, 2021, 8:56am UTC](https://discuss.ocaml.org/t/caqti-transaction-examples/8220 "2021-07-31T08:56:13Z")
EDIT: pauerkedal updated the oneshot documentation and it is now much clearer is anyone familiar with caqti and transactions? I’m getting errors like Invalid concurrent usage of PostgreSQL connection detected and: ca… --- ## [Getting OCaml Webmachine onto Tech Empower benchmarks - Caqti losing queries?](https://discuss.ocaml.org/t/getting-ocaml-webmachine-onto-tech-empower-benchmarks-caqti-losing-queries/6503)
**Author:** [@rbjorklin](https://discuss.ocaml.org/u/rbjorklin)\ **Replies:** 16\ **Last updated:** [October 19, 2020, 3:31pm UTC](https://discuss.ocaml.org/t/getting-ocaml-webmachine-onto-tech-empower-benchmarks-caqti-losing-queries/6503 "2020-10-19T15:31:26Z")
Hi! So first of all I’m an OCaml beginner with no previous experience in asynchronous programming. I’m struggling a bit with wrapping my head around the correct way to use Lwt. Both of these things have led to code quali… --- ## [A Lightweight OCaml Webapp Tutorial (Using Opium, Caqti, and Tyxml)](https://discuss.ocaml.org/t/a-lightweight-ocaml-webapp-tutorial-using-opium-caqti-and-tyxml/4967)
**Author:** [@shonfeder](https://discuss.ocaml.org/u/shonfeder)\ **Replies:** 6\ **Last updated:** [January 11, 2020, 8:46pm UTC](https://discuss.ocaml.org/t/a-lightweight-ocaml-webapp-tutorial-using-opium-caqti-and-tyxml/4967 "2020-01-11T20:46:42Z")
The tutorial is hosted on gitlab pages, out of this repository. I put this together in response to some requests for introductory material on the topic (here and on /r/ocaml. I don’t have much expertise to offer in this…