spark/databricks: out-of-catalog schema enumeration

NEWS.md

@@ -1,6 +1,6 @@
 # odbc (development version)
 
-
+* Spark SQL: Correctly enumerate schemas away from the current catalog (@detule, #614)
 * Modify `odbcDataType.Snowflake` to better reflect Snowflake Data Types documentation (@meztez, #599).
 * SQL Server: Specialize syntax in sqlCreateTable to avoid failures when
  writing to (new) local temp tables. (@detule, #601)

R/db.R

@@ -225,6 +225,27 @@ setMethod(
  }
  })
 
+# Spark SQL ----------------------------------------------------------------
+
+#' @details Databricks supports multiple catalogs. On the other hand
+#' the default implementation of `odbcConnectionSchemas` which routes through
+#' `SQLTables` is likely to enumerate the schemas in the currently active
+#' catalog only.
+#'
+#' This implementation will respect the `catalog_name` arrgument.
+#' @rdname odbcConnectionSchemas
+setMethod(
+ "odbcConnectionSchemas",
+ c("Spark SQL", "character"),
+ function(conn, catalog_name) {
+ res <- dbGetQuery(conn, paste0("SHOW SCHEMAS IN ", catalog_name))
+ if (nrow(res)) {
+ return(res$databaseName)
+ }
+ return(character())
+ }
+)
+
 # DB2 ----------------------------------------------------------------
 
 setClass("DB2/AIX64", where = class_cache)