MDEV-25259 JSON_TABLE: Illegal mix of collations upon executing query with...

MDEV-25259 JSON_TABLE: Illegal mix of collations upon executing query with combination of charsets via view.

The ::print method didn't print the explicitly specified charset.

mysql-test/suite/json/r/json_table.result

@@ -793,5 +793,15 @@ a	b	c	o
 DROP VIEW v2;
 DROP TABLE t1, t2;
 #
+# MDEV-25259 JSON_TABLE: Illegal mix of collations upon executing query with combination of charsets via view.
+#
+CREATE VIEW v AS
+SELECT * FROM JSON_TABLE(CONVERT('[]' USING dec8),
+'$' COLUMNS(b VARCHAR(8) CHARSET utf8 PATH '$')) AS jt2
+WHERE (CONVERT('[]' USING cp1256) = b);
+SELECT * FROM v;
+b
+DROP VIEW v;
+#
 # End of 10.6 tests
 #

mysql-test/suite/json/t/json_table.test

@@ -685,6 +685,19 @@ FROM
 DROP VIEW v2;
 DROP TABLE t1, t2;
 
+--echo #
+--echo # MDEV-25259 JSON_TABLE: Illegal mix of collations upon executing query with combination of charsets via view.
+--echo #
+
+CREATE VIEW v AS
+  SELECT * FROM JSON_TABLE(CONVERT('[]' USING dec8),
+      '$' COLUMNS(b VARCHAR(8) CHARSET utf8 PATH '$')) AS jt2
+  WHERE (CONVERT('[]' USING cp1256) = b);
+
+SELECT * FROM v;
+
+DROP VIEW v;
+
 --echo #
 --echo # End of 10.6 tests
 --echo #

sql/json_table.cc

@@ -1098,6 +1098,8 @@ int Json_table_column::print(THD *thd, Field **f, String *str)
     (*f)->sql_type(column_type);
 
     if (str->append(column_type) ||
+        (m_explicit_cs &&
+           (str->append(" CHARSET ") || str->append(m_explicit_cs->csname))) ||
         str->append(m_column_type == PATH ? " PATH " : " EXISTS PATH ") ||
         print_path(str, &m_path))
       return 1;