Populate Macaw options based on database type (#43460)

src/metabase/native_query_analyzer.clj

@@ -15,6 +15,7 @@
    [clojure.string :as str]
    [macaw.core :as macaw]
    [metabase.config :as config]
+   [metabase.driver.util :as driver.u]
    [metabase.native-query-analyzer.parameter-substitution :as nqa.sub]
    [metabase.native-query-analyzer.replacement :as nqa.replacement]
    [metabase.public-settings :as public-settings]
@@ -134,6 +135,42 @@
                                                     [:= :f.active true]
                                                     (into [:or] (map table-query tables))]}))))
 
+;; NOTE: In future we would want to replace [[considered-drivers]] and [[macaw-options]] with (a) driver method(s),
+;; but given that the interface with Macaw is still in a state of flux, and how simple the current configuration is,
+;; we defer extending the public interface and define the logic locally instead. Macaw itself is not battle tested
+;; outside this same narrow range of databases in any case.
+
+(def ^:private considered-drivers
+  "Since we are unable to ask basic questions of the driver hierarchy outside of that module, we need to repeat"
+  #{:mysql :sqlserver :h2 :sqlite :postgres :redshift})
+
+(defn- macaw-options
+  "Generate the options expected by Macaw based on the nature of the given driver."
+  [driver]
+  ;; If this isn't a driver we've considered, fallback to Macaw's conservative defaults.
+  (when (contains? considered-drivers driver)
+    ;; According to the SQL-92 specification, non-quoted identifiers should be case-insensitive, and the majority of
+    ;; engines are implemented this way.
+    ;;
+    ;; In practice there are exceptions, notably MySQL and SQL Server, where case sensitivity is a property of the
+    ;; underlying resource referenced by the identifier, and the case-sensitivity does not depend on whether the
+    ;; reference is quoted.
+    ;;
+    ;; For MySQL the case sensitivity of databases and tables depends on both the underlying
+    ;; file system, and a system variable used to initialize the database. For SQL Server it depends on the collation
+    ;; settings of the collection where the corresponding schema element is defined.
+    ;;
+    ;; For MySQL, columns and aliases can never be case-sensitive, and for SQL Server the default collation is case-
+    ;; insensitive too, so it makes sense to just treat all databases as case-insensitive as a whole.
+    ;;
+    ;; In future Macaw may support discriminating on the identifier type, in which case we could be more precise for
+    ;; these databases. Being 100% correct would require querying system variables and schema configuration however,
+    ;; which is likely a step too far in complexity.
+    {:case-insensitive?     true
+     ;; For both MySQL and SQL Server, whether identifiers are case-sensitive depends on database configuration only,
+     ;; and quoting has no effect on this, so we disable this option for consistency with `:case-insensitive?`.
+     :quotes-preserve-case? (not (#{:mysql :sqlserver} driver))}))
+
 (defn field-ids-for-sql
   "Returns a `{:direct #{...} :indirect #{...}}` map with field IDs that (may) be referenced in the given card's
   query. Errs on the side of optimism: i.e., it may return fields that are *not* in the query, and is unlikely to fail
@@ -146,7 +183,9 @@
              (:native query))
     (let [db-id        (:database query)
           sql-string   (:query (nqa.sub/replace-tags query))
-          parsed-query (macaw/query->components (macaw/parsed-query sql-string))
+          driver       (driver.u/database->driver db-id)
+          macaw-opts   (macaw-options driver)
+          parsed-query (macaw/query->components (macaw/parsed-query sql-string) macaw-opts)
           direct-ids   (direct-field-ids-for-query parsed-query db-id)
           indirect-ids (set/difference
                         (indirect-field-ids-for-query parsed-query db-id)