From 2c35d48173833a072d039eb6fd4a17adb260d3b2 Mon Sep 17 00:00:00 2001
From: Dirk Eddelbuettel <edd@debian.org>
Date: Tue, 2 Mar 2021 18:13:44 -0600
Subject: [PATCH 1/3] use estimated size when no result size was returned

---
 R/TileDBArray.R | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/R/TileDBArray.R b/R/TileDBArray.R
index efac91778b..f4487107e7 100644
--- a/R/TileDBArray.R
+++ b/R/TileDBArray.R
@@ -526,7 +526,11 @@ setMethod("[", "tiledb_array",
       libtiledb_query_result_buffer_elements(qryptr, name)
   }
   estsz <- mapply(getResultSize, allnames, allvarnum, MoreArgs=list(qryptr=qryptr), SIMPLIFY=TRUE)
-  resrv <- max(estsz, na.rm=TRUE)
+  if (any(!is.na(estsz))) {
+      resrv <- max(estsz, na.rm=TRUE)
+  } else {
+      resrv <- resrv/8                  # character case where bytesize of offset vector was used
+  }
 
   ## get results
   getResult <- function(buf, name, varnum, resrv, qryptr) {

From ce8c5f3caf45a20665b7a10c0a9cd97595fb577c Mon Sep 17 00:00:00 2001
From: Dirk Eddelbuettel <edd@debian.org>
Date: Thu, 4 Mar 2021 14:30:10 -0600
Subject: [PATCH 2/3] update NEWS

---
 inst/NEWS.md | 1 +
 1 file changed, 1 insertion(+)

diff --git a/inst/NEWS.md b/inst/NEWS.md
index b326aae52e..fc43ed8d7b 100644
--- a/inst/NEWS.md
+++ b/inst/NEWS.md
@@ -8,6 +8,7 @@
 
 * Two tests with datetime comparisons which fail only on one macOS system are now conditional (#216)
 
+* Result sets with all-character column now fall back to estimated result sizes (#217)
 
 
 # 0.9.0

From f8718d39c7963631dfb30e046e194bad5d0f4835 Mon Sep 17 00:00:00 2001
From: Dirk Eddelbuettel <edd@debian.org>
Date: Thu, 4 Mar 2021 14:48:00 -0600
Subject: [PATCH 3/3] add a unit test

---
 inst/tinytest/test_dataframe.R | 15 ++++++++++++++-
 1 file changed, 14 insertions(+), 1 deletion(-)

diff --git a/inst/tinytest/test_dataframe.R b/inst/tinytest/test_dataframe.R
index 846bb7d20a..e3321cef0e 100644
--- a/inst/tinytest/test_dataframe.R
+++ b/inst/tinytest/test_dataframe.R
@@ -70,7 +70,6 @@ expect_equal(df, newdf[,-1])
 
 
 ## test dense with non-default index columm
-#exit_file("not finished")
 uri <- tempfile()
 set.seed(42)
 rows <- 50L
@@ -233,3 +232,17 @@ if (getRversion() < '4.0.0') {
     val$B <- as.character(val$B)
 }
 expect_equal(dat, val)
+
+## array with char only columns in dimension and attribute, used to error before #217
+N <- 20
+D <- data.frame(sample=paste(LETTERS[1:N], as.character(sort(trunc(runif(N, 100, 200)))), sep=""),
+                header=paste(LETTERS[1:N], as.character(sort(trunc(runif(N, 10000, 20000)))), sep=""),
+                stringsAsFactors=FALSE)
+uri <- tempfile()
+fromDataFrame(D, uri, col_index=1, sparse=TRUE)
+chk <- tiledb_array(uri, as.data.frame=TRUE)
+if (getRversion() < '4.0.0') {
+    chk$sample <- as.character(chk$sample)
+    chk$header <- as.character(chk$header)
+}
+expect_equal(D, chk[])