From 330d7794861099fbbf2fb6e49d7287565d12750a Mon Sep 17 00:00:00 2001
From: Matthew Bellew <matthewb@labkey.com>
Date: Wed, 11 Feb 2026 16:43:37 -0800
Subject: [PATCH] Postgres validate after LabKey parse

---
 query/src/org/labkey/query/controllers/LabKeySql.md   |  7 ++++---
 .../org/labkey/query/controllers/QueryController.java | 11 ++++++++++-
 2 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/query/src/org/labkey/query/controllers/LabKeySql.md b/query/src/org/labkey/query/controllers/LabKeySql.md
index 82f4e45ca78..e39099d2f76 100644
--- a/query/src/org/labkey/query/controllers/LabKeySql.md
+++ b/query/src/org/labkey/query/controllers/LabKeySql.md
@@ -94,12 +94,13 @@ You can write queries that access data from different folders within the LabKey
 LabKey SQL supports **parameterized queries** to improve security and reusability.
 
 * **Syntax:**
-  `PARAMETERS(param1, param2) SELECT * FROM table WHERE column = param1`
+  `PARAMETERS(param1 type, param2 type DEFAULT value) SELECT * FROM table WHERE column = param1`
 * **Functionality:**
-  The `PARAMETERS` keyword declares parameters that can be passed into the query.
+  The `PARAMETERS` keyword declares parameters that can be passed into the query.  If a DEFAULT is
+  not specified, the value will default to NULL.
 * **Example:** A query with two parameters, `MinTemp` and `MinWeight`:
   ```sql
-  PARAMETERS(MinTemp double, MinWeight double)
+  PARAMETERS(MinTemp double, MinWeight double DEFAULT 0.0)
   SELECT
     ParticipantID,
     temperature_C,
diff --git a/query/src/org/labkey/query/controllers/QueryController.java b/query/src/org/labkey/query/controllers/QueryController.java
index 0d14f2a7b27..fe0fa0a6c18 100644
--- a/query/src/org/labkey/query/controllers/QueryController.java
+++ b/query/src/org/labkey/query/controllers/QueryController.java
@@ -132,6 +132,7 @@
 import org.labkey.api.data.SchemaTableInfo;
 import org.labkey.api.data.ShowRows;
 import org.labkey.api.data.SimpleFilter;
+import org.labkey.api.data.SqlExecutor;
 import org.labkey.api.data.SqlSelector;
 import org.labkey.api.data.TSVWriter;
 import org.labkey.api.data.Table;
@@ -8920,9 +8921,17 @@ public Object execute(SqlPromptForm form, BindException errors) throws Exception
                             if (warning.isPresent())
                                 throw warning.get();
                         }
+                        // if that worked, let have the DB check it too
+                        if (ti.getSqlDialect().isPostgreSQL())
+                        {
+                            // CONSIDER: will this work with LabKey SQL named parameters?
+                            SQLFragment sql = new SQLFragment("PREPARE validate AS SELECT * FROM ").append(ti.getFromSQL("MYVALIDATEQUERY__"));
+                            new SqlExecutor(ti.getSchema().getScope()).execute(sql);
+                        }
                     }
-                    catch (QueryException x)
+                    catch (Exception x)
                     {
+                        // CONSIDER remove line line/character information from DB errors as they won't match the LabKey SQL
                         String validationPrompt = "That SQL caused the " + (x instanceof QueryParseWarning ? "warning" : "error") + " below, can you attempt to fix this?\n```" + x.getMessage() + "```";
                         responses = McpService.get().sendMessageEx(chatSession, validationPrompt);
                         var newSqlResponse = extractSql(responses);