nanodbc: handle db2 xml data (#917)

* nanodbc: handle db2 xml data

See upstream: nanodbc/nanodbc#430

* Fix merge derp

* Update NEWS

* tests: update _snaps/utils

* tests: fixup datetimeoffset/pro driver failure

* tests: update _snaps/utils again

Author: detule

NEWS.md

@@ -1,11 +1,13 @@
 # odbc (development version)
 
-* SQL Server: Support for `DATETIMEOFFSET` data type (#918). 
-
 * Fix hang when parsing exceptionally long database errors (#916).
 
 * DB2: Fix error when writing to temp tables (#910).
 
+* DB2: Add support for `DB2_XML` (#913).
+
+* SQL Server: Support for `DATETIMEOFFSET` data type (#918).
+
 * SQL Server: Fix issues with argument propagation in bespoke
   S4 methods (#906).
 

src/nanodbc/nanodbc.cpp

@@ -65,6 +65,9 @@
 #include <sqlext.h>
 
 // Driver specific SQL data type defines.
+#ifndef SQL_DB2_XML
+#define SQL_DB2_XML (-370)
+#endif
 // Microsoft has -150 thru -199 reserved for Microsoft SQL Server Native Client driver usage.
 // Originally, defined in sqlncli.h (old SQL Server Native Client driver)
 // and msodbcsql.h (new Microsoft ODBC Driver for SQL Server)
@@ -2986,6 +2989,7 @@ class result::result_impl
             case SQL_VARBINARY:
             case SQL_LONGVARBINARY:
             case SQL_SS_UDT: // MSDN: Essentially, UDT is a varbinary type with additional metadata.
+            case SQL_DB2_XML:
                 col.ctype_ = SQL_C_BINARY;
                 col.blob_ = true;
                 col.clen_ = 0;

src/odbc_result.cpp

@@ -8,6 +8,9 @@
 #ifndef SQL_SS_TIME2
 #define SQL_SS_TIME2 (-154)
 #endif
+#ifndef SQL_DB2_XML
+#define SQL_DB2_XML (-370)
+#endif
 #ifndef SQL_SS_TIMESTAMPOFFSET
 #define SQL_SS_TIMESTAMPOFFSET (-155)
 #endif
@@ -755,6 +758,7 @@ std::vector<r_type> odbc_result::column_types(nanodbc::result const& r) {
     case SQL_BINARY:
     case SQL_VARBINARY:
     case SQL_LONGVARBINARY:
+    case SQL_DB2_XML:
       types.push_back(raw_t);
       break;
     default:

tests/testthat/_snaps/utils.md

@@ -28,7 +28,7 @@
       ! ODBC failed with error 00000 from [unixODBC][Driver Manager].
       x Data source name not found and no default driver specified
       i See `?odbc::odbcListDataSources()` to learn more.
-      i From 'nanodbc/nanodbc.cpp:1156'.
+      i From 'nanodbc/nanodbc.cpp:1159'.
 
 ---
 
@@ -39,7 +39,7 @@
       ! ODBC failed with error 00000 from [SQLite].
       x no such table: boopbopbopbeep (1)
       * <SQL> 'SELECT * FROM boopbopbopbeep'
-      i From 'nanodbc/nanodbc.cpp:1732'.
+      i From 'nanodbc/nanodbc.cpp:1735'.
 
 # rethrow_database_error() errors well when parse_database_error() fails
 

tests/testthat/test-driver-sql-server.R

@@ -385,7 +385,7 @@ test_that("DATETIMEOFFSET", {
     field.types = list("tz_char" = "VARCHAR(50)", "tz" = "DATETIMEOFFSET"), overwrite = TRUE)
   res <- DBI::dbReadTable(con, tbl)
   expect_s3_class(res[[2]], "POSIXct")
-  expect_equal(as.double(res[[2]][1] - as.POSIXct(res[[1]][1]), units = "hours"), 2)
+  expect_equal(as.double(res[[2]][1] - as.POSIXct(res[[1]][1]), units = "hours"), 2, tolerance = 1E-4)
 })
 
 test_that("package:odbc roundtrip test", {