From 5d6d28f274e38a7691fa30a6674452ad6c8870fd Mon Sep 17 00:00:00 2001
From: Alexander Barkov <bar@mariadb.com>
Date: Fri, 11 Oct 2019 22:19:30 +0400
Subject: [PATCH] MDEV-20798 Conversion from INET6 to other types performed
 without errors or warnings

---
 .../mysql-test/type_inet/type_inet6.result    | 300 ++++++++++++++++++
 .../mysql-test/type_inet/type_inet6.test      | 284 +++++++++++++++++
 plugin/type_inet/sql_type_inet.cc             |  22 +-
 plugin/type_inet/sql_type_inet.h              |   1 +
 sql/field.h                                   |   8 +
 sql/sql_type.h                                |  10 +
 6 files changed, 610 insertions(+), 15 deletions(-)

diff --git a/plugin/type_inet/mysql-test/type_inet/type_inet6.result b/plugin/type_inet/mysql-test/type_inet/type_inet6.result
index c6d12c06a4c..9e3601e414b 100644
--- a/plugin/type_inet/mysql-test/type_inet/type_inet6.result
+++ b/plugin/type_inet/mysql-test/type_inet/type_inet6.result
@@ -1580,6 +1580,280 @@ a
 2001:db8::ff00:42:8329
 DROP TABLE t1;
 #
+# SET from INET6 to INET6
+#
+CREATE TABLE t1 (a INET6, b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+#
+# SET from INET6 to numeric
+#
+CREATE TABLE t1 (a INET6, b INT);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect integer value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b DOUBLE);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect double value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b DECIMAL(32,0));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect decimal value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b YEAR);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect integer value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+#
+# SET from numeric to INET6
+#
+CREATE TABLE t1 (a INT, b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '1' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a DOUBLE, b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '1' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a DECIMAL(32,0), b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '1' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a YEAR, b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '2001' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+#
+# SET from INET6 to temporal
+#
+CREATE TABLE t1 (a INET6, b TIME);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect time value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b DATE);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect date value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b DATETIME);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect datetime value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b TIMESTAMP NULL DEFAULT NULL);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect datetime value: 'ffff::ffff' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+#
+# SET from temporal to INET6
+#
+CREATE TABLE t1 (a TIME, b INET6);
+INSERT INTO t1 VALUES ('00:00:00', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '00:00:00' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a DATE, b INET6);
+INSERT INTO t1 VALUES ('2001-01:01', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '2001-01-01' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a DATETIME, b INET6);
+INSERT INTO t1 VALUES ('2001-01-01 10:20:30', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '2001-01-01 10:20:30' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+CREATE TABLE t1 (a TIMESTAMP, b INET6);
+INSERT INTO t1 VALUES ('2001-01-01 10:20:30', NULL);
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect inet6 value: '2001-01-01 10:20:30' for column `test`.`t1`.`b` at row 1
+SELECT b FROM t1;
+b
+NULL
+DROP TABLE t1;
+#
+# SET from INET6 to character string
+#
+CREATE TABLE t1 (a INET6, b CHAR(39));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b VARCHAR(39));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b TEXT);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b ENUM('ffff::ffff'));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b SET('ffff::ffff'));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+#
+# SET from character string to INET6
+#
+CREATE TABLE t1 (a CHAR(39), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a VARCHAR(39), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a TEXT, b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a ENUM('ffff::ffff'), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a SET('ffff::ffff'), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+#
+# SET from INET6 to binary
+#
+CREATE TABLE t1 (a INET6, b BINARY(16));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT HEX(b) FROM t1;
+HEX(b)
+FFFF000000000000000000000000FFFF
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b VARBINARY(39));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT HEX(b) FROM t1;
+HEX(b)
+FFFF000000000000000000000000FFFF
+DROP TABLE t1;
+CREATE TABLE t1 (a INET6, b BLOB);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT HEX(b) FROM t1;
+HEX(b)
+FFFF000000000000000000000000FFFF
+DROP TABLE t1;
+#
+# SET from binary to INET6
+#
+CREATE TABLE t1 (a BINARY(16), b INET6);
+INSERT INTO t1 VALUES (CONCAT(0xFFFF,REPEAT(0x0000,6),0xFFFF), NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a VARBINARY(16), b INET6);
+INSERT INTO t1 VALUES (CONCAT(0xFFFF,REPEAT(0x0000,6),0xFFFF), NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+CREATE TABLE t1 (a BLOB, b INET6);
+INSERT INTO t1 VALUES (CONCAT(0xFFFF,REPEAT(0x0000,6),0xFFFF), NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+b
+ffff::ffff
+DROP TABLE t1;
+#
 # Limit clause parameter
 # TODO: this should fail.
 # The test for a valid data type should be moved
@@ -1631,3 +1905,29 @@ INSERT INTO t1 VALUES ('::');
 SELECT CAST(a AS FLOAT) FROM t1;
 ERROR HY000: Illegal parameter data type inet6 for operation 'float_typecast'
 DROP TABLE t1;
+#
+# MDEV-20798 Conversion from INET6 to other types performed without errors or warnings
+#
+CREATE TABLE t1 (a INET6, b INT);
+INSERT INTO t1 (a) VALUES ('::');
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect integer value: '::' for column `test`.`t1`.`b` at row 1
+SELECT * FROM t1;
+a	b
+::	NULL
+DROP TABLE t1;
+SET timestamp=UNIX_TIMESTAMP('2001-01-01 10:20:30');
+CREATE TABLE t1 (a INET6, b TIMESTAMP);
+INSERT INTO t1 (a) VALUES ('::');
+UPDATE t1 SET b=a;
+ERROR 22007: Incorrect datetime value: '::' for column `test`.`t1`.`b` at row 1
+SELECT * FROM t1;
+a	b
+::	2001-01-01 10:20:30
+DROP TABLE t1;
+SET timestamp=DEFAULT;
+CREATE OR REPLACE TABLE t1 (a INET6);
+INSERT INTO t1 (a) VALUES ('::');
+ALTER TABLE t1 MODIFY a DATE;
+ERROR 22007: Incorrect date value: '::' for column `test`.`t1`.`a` at row 1
+DROP TABLE t1;
diff --git a/plugin/type_inet/mysql-test/type_inet/type_inet6.test b/plugin/type_inet/mysql-test/type_inet/type_inet6.test
index 3743bd0f9ed..a17f5dd69f7 100644
--- a/plugin/type_inet/mysql-test/type_inet/type_inet6.test
+++ b/plugin/type_inet/mysql-test/type_inet/type_inet6.test
@@ -1065,6 +1065,264 @@ SELECT a FROM t1;
 DROP TABLE t1;
 
 
+--echo #
+--echo # SET from INET6 to INET6
+--echo #
+
+CREATE TABLE t1 (a INET6, b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+--echo #
+--echo # SET from INET6 to numeric
+--echo #
+
+CREATE TABLE t1 (a INET6, b INT);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE_FOR_FIELD
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b DOUBLE);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE_FOR_FIELD
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b DECIMAL(32,0));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE_FOR_FIELD
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b YEAR);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE_FOR_FIELD
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from numeric to INET6
+--echo #
+
+CREATE TABLE t1 (a INT, b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a DOUBLE, b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a DECIMAL(32,0), b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a YEAR, b INET6);
+INSERT INTO t1 VALUES (1, NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from INET6 to temporal
+--echo #
+
+CREATE TABLE t1 (a INET6, b TIME);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b DATE);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b DATETIME);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b TIMESTAMP NULL DEFAULT NULL);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from temporal to INET6
+--echo #
+
+CREATE TABLE t1 (a TIME, b INET6);
+INSERT INTO t1 VALUES ('00:00:00', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a DATE, b INET6);
+INSERT INTO t1 VALUES ('2001-01:01', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a DATETIME, b INET6);
+INSERT INTO t1 VALUES ('2001-01-01 10:20:30', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a TIMESTAMP, b INET6);
+INSERT INTO t1 VALUES ('2001-01-01 10:20:30', NULL);
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from INET6 to character string
+--echo #
+
+CREATE TABLE t1 (a INET6, b CHAR(39));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b VARCHAR(39));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b TEXT);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b ENUM('ffff::ffff'));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b SET('ffff::ffff'));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from character string to INET6
+--echo #
+
+CREATE TABLE t1 (a CHAR(39), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a VARCHAR(39), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a TEXT, b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a ENUM('ffff::ffff'), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a SET('ffff::ffff'), b INET6);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from INET6 to binary
+--echo #
+
+CREATE TABLE t1 (a INET6, b BINARY(16));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT HEX(b) FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b VARBINARY(39));
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT HEX(b) FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a INET6, b BLOB);
+INSERT INTO t1 VALUES ('ffff::ffff', NULL);
+UPDATE t1 SET b=a;
+SELECT HEX(b) FROM t1;
+DROP TABLE t1;
+
+
+--echo #
+--echo # SET from binary to INET6
+--echo #
+
+CREATE TABLE t1 (a BINARY(16), b INET6);
+INSERT INTO t1 VALUES (CONCAT(0xFFFF,REPEAT(0x0000,6),0xFFFF), NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a VARBINARY(16), b INET6);
+INSERT INTO t1 VALUES (CONCAT(0xFFFF,REPEAT(0x0000,6),0xFFFF), NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+CREATE TABLE t1 (a BLOB, b INET6);
+INSERT INTO t1 VALUES (CONCAT(0xFFFF,REPEAT(0x0000,6),0xFFFF), NULL);
+UPDATE t1 SET b=a;
+SELECT b FROM t1;
+DROP TABLE t1;
+
+
 --echo #
 --echo # Limit clause parameter
 --echo # TODO: this should fail.
@@ -1127,3 +1385,29 @@ INSERT INTO t1 VALUES ('::');
 --error ER_ILLEGAL_PARAMETER_DATA_TYPE_FOR_OPERATION
 SELECT CAST(a AS FLOAT) FROM t1;
 DROP TABLE t1;
+
+--echo #
+--echo # MDEV-20798 Conversion from INET6 to other types performed without errors or warnings
+--echo #
+
+CREATE TABLE t1 (a INET6, b INT);
+INSERT INTO t1 (a) VALUES ('::');
+--error ER_TRUNCATED_WRONG_VALUE_FOR_FIELD
+UPDATE t1 SET b=a;
+SELECT * FROM t1;
+DROP TABLE t1;
+
+SET timestamp=UNIX_TIMESTAMP('2001-01-01 10:20:30');
+CREATE TABLE t1 (a INET6, b TIMESTAMP);
+INSERT INTO t1 (a) VALUES ('::');
+--error ER_TRUNCATED_WRONG_VALUE
+UPDATE t1 SET b=a;
+SELECT * FROM t1;
+DROP TABLE t1;
+SET timestamp=DEFAULT;
+
+CREATE OR REPLACE TABLE t1 (a INET6);
+INSERT INTO t1 (a) VALUES ('::');
+--error ER_TRUNCATED_WRONG_VALUE
+ALTER TABLE t1 MODIFY a DATE;
+DROP TABLE t1;
diff --git a/plugin/type_inet/sql_type_inet.cc b/plugin/type_inet/sql_type_inet.cc
index 97e433cb053..7f9adf1d299 100644
--- a/plugin/type_inet/sql_type_inet.cc
+++ b/plugin/type_inet/sql_type_inet.cc
@@ -802,23 +802,15 @@ public:
   int save_in_field(Field *to) override
   {
     // INSERT INTO t2 (different_field_type) SELECT inet6_field FROM t1;
-    switch (to->cmp_type()) {
-    case INT_RESULT:
-    case REAL_RESULT:
-    case DECIMAL_RESULT:
-    case TIME_RESULT:
+    if (to->charset() == &my_charset_bin &&
+        dynamic_cast<const Type_handler_general_purpose_string*>
+          (to->type_handler()))
     {
-      my_decimal buff;
-      return to->store_decimal(val_decimal(&buff));
+      NativeBufferInet6 res;
+      val_native(&res);
+      return to->store(res.ptr(), res.length(), &my_charset_bin);
     }
-    case STRING_RESULT:
-      return save_in_field_str(to);
-    case ROW_RESULT:
-      break;
-    }
-    DBUG_ASSERT(0);
-    to->reset();
-    return 0;
+    return save_in_field_str(to);
   }
   Copy_func *get_copy_func(const Field *from) const override
   {
diff --git a/plugin/type_inet/sql_type_inet.h b/plugin/type_inet/sql_type_inet.h
index 485828fa5b6..970c3b63a3e 100644
--- a/plugin/type_inet/sql_type_inet.h
+++ b/plugin/type_inet/sql_type_inet.h
@@ -393,6 +393,7 @@ public:
   bool can_return_text() const override { return true; }
   bool can_return_date() const override { return false; }
   bool can_return_time() const override { return false; }
+  bool convert_to_binary_using_val_native() const override { return true; }
 
   uint Item_time_precision(THD *thd, Item *item) const override
   {
diff --git a/sql/field.h b/sql/field.h
index a0d8476df94..3d9cfe92346 100644
--- a/sql/field.h
+++ b/sql/field.h
@@ -4168,6 +4168,14 @@ public:
   }
   int  store_field(Field *from) override
   {                                             // Be sure the value is stored
+    if (field_charset() == &my_charset_bin &&
+        from->type_handler()->convert_to_binary_using_val_native())
+    {
+      NativeBuffer<64> tmp;
+      from->val_native(&tmp);
+      value.copy(tmp.ptr(), tmp.length(), &my_charset_bin);
+      return store(value.ptr(), value.length(), &my_charset_bin);
+    }
     from->val_str(&value);
     if (table->copy_blobs ||
         (!value.is_alloced() && from->is_varchar_and_in_write_set()))
diff --git a/sql/sql_type.h b/sql/sql_type.h
index ac9b7c962cc..54356c09b09 100644
--- a/sql/sql_type.h
+++ b/sql/sql_type.h
@@ -3411,6 +3411,16 @@ public:
   {
     return false;
   }
+  /*
+    If operations such as:
+      UPDATE t1 SET binary_string_field=this_type_field;
+    should store this_type_field->val_native() rather than
+    this_type_field->val_str().
+  */
+  virtual bool convert_to_binary_using_val_native() const
+  {
+    return false;
+  }
   virtual bool is_timestamp_type() const
   {
     return false;