oracle: tables: do not escape when using exact query (#712)

* oracle: tables: do not escape when using exact query

* code-review: tests and news

---------

Co-authored-by: Hadley Wickham <h.wickham@gmail.com>

NEWS.md

@@ -1,5 +1,11 @@
 # odbc (development version)
 
+* Oracle: Fix checking for existence when identifier components
+  contain underscores (@detule, #712).
+
+* databricks: Fix schema enumeration in connections pane
+  (@detule, #715).
+
 * SQL Server Fix `dbExists` for temporary table (@meztez, #724).
 
 # odbc 1.4.1

R/utils.R

@@ -103,6 +103,13 @@ convertWildCards <- function(val) {
   gsub("_", "(.)", val)
 }
 
+# Will return " AND key [= | LIKE] value"
+# where "=" or "LIKE" is chosen depending
+# on the the `exact` argument, and whether
+# the `value` contains any wild card characters.
+#
+# Note, wild cards are not escaped in `value`
+# as part of this call.
 getSelector <- function(key, value, exact) {
   if (is.null(value)) {
     return("")
@@ -112,9 +119,6 @@ getSelector <- function(key, value, exact) {
     isPatternValue(value)) {
     comp <- " LIKE "
   }
-  if (exact && (value != "%")) {
-    value <- escapePattern(value)
-  }
   value <- paste0("'", value, "'")
 
   paste0(" AND ", key, comp, value)

tests/testthat/test-utils.R

@@ -35,4 +35,21 @@ test_that("id_field checks inputs", {
     id_field(DBI::Id("a"), "foo")
     id_field(DBI::Id("a", "b", "c", "d"))
   })
+
+test_that("getSelector", {
+  # If no wild cards are detected always use exact comparison / ignore `exact` argument
+  expect_equal(getSelector("mykey", "myvalue", exact = TRUE), " AND mykey = 'myvalue'")
+  expect_equal(getSelector("mykey", "myvalue", exact = FALSE), " AND mykey = 'myvalue'")
+
+  # If `value` contains wild cards, respect `exact`argument
+  expect_equal(getSelector("mykey", "myvalu_", exact = TRUE), " AND mykey = 'myvalu_'")
+  expect_equal(getSelector("mykey", "myvalu_", exact = FALSE), " AND mykey LIKE 'myvalu_'")
+
+  expect_equal(getSelector("mykey", "myvalu%", exact = TRUE), " AND mykey = 'myvalu%'")
+  expect_equal(getSelector("mykey", "myvalu%", exact = FALSE), " AND mykey LIKE 'myvalu%'")
+
+  # ... unless argument is '%' - always use 'LIKE' since this is most likely the
+  # desired comparison / ignore `exact` argument
+  expect_equal(getSelector("mykey", "%", exact = TRUE), " AND mykey LIKE '%'")
+  expect_equal(getSelector("mykey", "%", exact = FALSE), " AND mykey LIKE '%'")
 })