Fix for Bug#35469: server crash with LOAD DATA INFILE to a VIEW.

The problem was that LOAD DATA code (sql_load.cc) didn't take into
account that there may be items, representing references to other
columns. This is a usual case in views. The crash happened because
Item_direct_view_ref was casted to Item_user_var_as_out_param,
which is not a base class.

The fix is to
  1) Handle references properly;
  2) Ensure that an item is treated as a user variable only when
     it is a user variable indeed;
  3) Report an error if LOAD DATA is used to load data into
     non-updatable column.


mysql-test/r/loaddata.result:
  Update result file.
mysql-test/t/loaddata.test:
  Add a test case form Bug#35469: server crash with
  LOAD DATA INFILE to a VIEW.
sql/share/errmsg.txt:
  Introduce a new error.
sql/sql_load.cc:
  Handle reference-items properly.
mysql-test/std_data/bug35649.data:
  Add a data file for the test case.

1 files changed, 76 insertions, 0 deletions

diff --git a/mysql-test/r/loaddata.result b/mysql-test/r/loaddata.result
index 7fff2700779..156a78eb627 100644
--- a/mysql-test/r/loaddata.result
+++ b/mysql-test/r/loaddata.result
@@ -252,3 +252,79 @@ SELECT * FROM t1;
 c1	c2	c3	c4
 10	1970-02-01 01:02:03	1.1e-100	1.1e+100
 DROP TABLE t1;
+
+# --
+# -- Bug#35469: server crash with LOAD DATA INFILE to a VIEW.
+# --
+
+DROP TABLE IF EXISTS t1;
+DROP VIEW IF EXISTS v1;
+DROP VIEW IF EXISTS v2;
+DROP VIEW IF EXISTS v3;
+
+CREATE TABLE t1(c1 INT, c2 VARCHAR(255));
+
+CREATE VIEW v1 AS SELECT * FROM t1;
+CREATE VIEW v2 AS SELECT 1 + 2 AS c0, c1, c2 FROM t1;
+CREATE VIEW v3 AS SELECT 1 AS d1, 2 AS d2;
+
+LOAD DATA INFILE '../std_data_ln/bug35649.data' INTO TABLE v1
+FIELDS ESCAPED BY '\\'
+  TERMINATED BY ','
+  ENCLOSED BY '"'
+  LINES TERMINATED BY '\n' (c1, c2);
+
+SELECT * FROM t1;
+c1	c2
+1	 "string1"
+2	 "string2"
+3	 "string3"
+
+SELECT * FROM v1;
+c1	c2
+1	 "string1"
+2	 "string2"
+3	 "string3"
+
+DELETE FROM t1;
+
+LOAD DATA INFILE '../std_data_ln/bug35649.data' INTO TABLE v2
+FIELDS ESCAPED BY '\\'
+  TERMINATED BY ','
+  ENCLOSED BY '"'
+  LINES TERMINATED BY '\n' (c1, c2);
+
+SELECT * FROM t1;
+c1	c2
+1	 "string1"
+2	 "string2"
+3	 "string3"
+
+SELECT * FROM v2;
+c0	c1	c2
+3	1	 "string1"
+3	2	 "string2"
+3	3	 "string3"
+
+DELETE FROM t1;
+
+LOAD DATA INFILE '../std_data_ln/bug35649.data' INTO TABLE v2
+FIELDS ESCAPED BY '\\'
+  TERMINATED BY ','
+  ENCLOSED BY '"'
+  LINES TERMINATED BY '\n' (c0, c2);
+ERROR HY000: Invalid column reference (v2.c0) in LOAD DATA
+
+LOAD DATA INFILE '../std_data_ln/bug35649.data' INTO TABLE v3
+FIELDS ESCAPED BY '\\'
+  TERMINATED BY ','
+  ENCLOSED BY '"'
+  LINES TERMINATED BY '\n' (d1, d2);
+ERROR HY000: The target table v3 of the LOAD is not updatable
+
+DROP TABLE t1;
+DROP VIEW v1;
+DROP VIEW v2;
+DROP VIEW v3;
+
+# -- End of Bug#35469.