docs(accursed): add cursed knowledge page (#10031)

We have a lot of catching up to do, but we can at least note down these
horrors as we reencounter them.

docs/_quarto.yml

@@ -181,6 +181,10 @@ website:
             - reference/Repr.qmd
             - reference/SQL.qmd
 
+        - section: Cursed Knowledge
+          contents:
+            - reference/cursed_knowledge.qmd
+
 format:
   html:
     theme:

docs/reference/cursed_knowledge.qmd

@@ -0,0 +1,16 @@
+# Cursed Knowledge
+
+Cursed knowledge the Ibis developers have acquired via battling with many, many
+execution engines.
+
+## Oracle
+
+* Oracle's `LTRIM` and `RTRIM` functions accept a _set_ of whitespace (or other)
+  characters to remove from the left-, and right-hand-side sides of the input
+  string, but the `TRIM` function only accepts a single character to remove.
+
+## Impala
+
+* Impala's `LTRIM` and `RTRIM` functions accept a _set_ of whitespace (or other)
+  characters to remove from the left-, and right-hand-side sides of the input
+  string, but the `TRIM` function only removes _spaces_.