ddl: allow more charset/collation modifications for database/table (#…

…10958)
pingcap · Jul 5, 2019 · 4a8d083 · 4a8d083
1 parent 842acd8
commit 4a8d083
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Showing 2 changed files with 23 additions and 14 deletions.
diff --git a/ddl/db_integration_test.go b/ddl/db_integration_test.go
@@ -319,17 +319,17 @@ func (s *testIntegrationSuite) TestChangingTableCharset(c *C) {
  tk.MustExec("drop table t;")
  tk.MustExec("create table t(a varchar(10)) charset utf8")
  tk.MustExec("alter table t convert to charset utf8mb4;")
- checkCharset := func() {
+ checkCharset := func(chs, coll string) {
  tbl := testGetTableByName(c, tk.Se, "test", "t")
  c.Assert(tbl, NotNil)
- c.Assert(tbl.Meta().Charset, Equals, charset.CharsetUTF8MB4)
- c.Assert(tbl.Meta().Collate, Equals, charset.CollationUTF8MB4)
+ c.Assert(tbl.Meta().Charset, Equals, chs)
+ c.Assert(tbl.Meta().Collate, Equals, coll)
  for _, col := range tbl.Meta().Columns {
- c.Assert(col.Charset, Equals, charset.CharsetUTF8MB4)
- c.Assert(col.Collate, Equals, charset.CollationUTF8MB4)
+ c.Assert(col.Charset, Equals, chs)
+ c.Assert(col.Collate, Equals, coll)
  }
  }
- checkCharset()
+ checkCharset(charset.CharsetUTF8MB4, charset.CollationUTF8MB4)
 
  // Test when column charset can not convert to the target charset.
  tk.MustExec("drop table t;")
@@ -338,11 +338,16 @@ func (s *testIntegrationSuite) TestChangingTableCharset(c *C) {
  c.Assert(err, NotNil)
  c.Assert(err.Error(), Equals, "[ddl:210]unsupported modify charset from ascii to utf8mb4")
 
+ tk.MustExec("drop table t;")
+ tk.MustExec("create table t(a varchar(10) character set utf8) charset utf8")
+ tk.MustExec("alter table t convert to charset utf8 collate utf8_general_ci;")
+ checkCharset(charset.CharsetUTF8, "utf8_general_ci")
+
  // Test when table charset is equal to target charset but column charset is not equal.
  tk.MustExec("drop table t;")
  tk.MustExec("create table t(a varchar(10) character set utf8) charset utf8mb4")
- tk.MustExec("alter table t convert to charset utf8mb4;")
- checkCharset()
+ tk.MustExec("alter table t convert to charset utf8mb4 collate utf8mb4_general_ci;")
+ checkCharset(charset.CharsetUTF8MB4, "utf8mb4_general_ci")
 
  // Mock table info with charset is "". Old TiDB maybe create table with charset is "".
  db, ok := domain.GetDomain(tk.Se).InfoSchema().SchemaByName(model.NewCIStr("test"))
@@ -375,7 +380,7 @@ func (s *testIntegrationSuite) TestChangingTableCharset(c *C) {
  c.Assert(tbl.Meta().Collate, Equals, "")
  // Test when table charset is "", this for compatibility.
  tk.MustExec("alter table t convert to charset utf8mb4;")
- checkCharset()
+ checkCharset(charset.CharsetUTF8MB4, charset.CollationUTF8MB4)
 
  // Test when column charset is "".
  tbl = testGetTableByName(c, tk.Se, "test", "t")
@@ -390,7 +395,7 @@ func (s *testIntegrationSuite) TestChangingTableCharset(c *C) {
  c.Assert(tbl.Meta().Columns[0].Charset, Equals, "")
  c.Assert(tbl.Meta().Columns[0].Collate, Equals, "")
  tk.MustExec("alter table t convert to charset utf8mb4;")
- checkCharset()
+ checkCharset(charset.CharsetUTF8MB4, charset.CollationUTF8MB4)
 
  tk.MustExec("drop table t")
  tk.MustExec("create table t (a blob) character set utf8;")
@@ -743,10 +748,12 @@ func (s *testIntegrationSuite) TestChangingDBCharset(c *C) {
  _, err := tk.Exec(fc.stmt)
  c.Assert(err.Error(), Equals, fc.errMsg, Commentf("%v", fc.stmt))
  }
+ tk.MustExec("ALTER SCHEMA CHARACTER SET = 'utf8' COLLATE = 'utf8_unicode_ci'")
+ verifyDBCharsetAndCollate("alterdb2", "utf8", "utf8_unicode_ci")
 
  tk.MustExec("ALTER SCHEMA CHARACTER SET = 'utf8mb4'")
  verifyDBCharsetAndCollate("alterdb2", "utf8mb4", "utf8mb4_bin")
 
- _, err := tk.Exec("ALTER SCHEMA CHARACTER SET = 'utf8mb4' COLLATE = 'utf8mb4_general_ci'")
- c.Assert(err.Error(), Equals, "[ddl:210]unsupported modify collate from utf8mb4_bin to utf8mb4_general_ci")
+ tk.MustExec("ALTER SCHEMA CHARACTER SET = 'utf8mb4' COLLATE = 'utf8mb4_general_ci'")
+ verifyDBCharsetAndCollate("alterdb2", "utf8mb4", "utf8mb4_general_ci")
 }
diff --git a/ddl/ddl_api.go b/ddl/ddl_api.go
@@ -1759,8 +1759,10 @@ func modifiableCharsetAndCollation(toCharset, toCollate, origCharset, origCollat
  if !charset.ValidCharsetAndCollation(toCharset, toCollate) {
  return ErrUnknownCharacterSet.GenWithStack("Unknown character set: '%s', collation: '%s'", toCharset, toCollate)
  }
- if toCharset == charset.CharsetUTF8MB4 && origCharset == charset.CharsetUTF8 {
- // TiDB only allow utf8 to be changed to utf8mb4.
+ if (origCharset == charset.CharsetUTF8 && toCharset == charset.CharsetUTF8MB4) ||
+ (origCharset == charset.CharsetUTF8 && toCharset == charset.CharsetUTF8) ||
+ (origCharset == charset.CharsetUTF8MB4 && toCharset == charset.CharsetUTF8MB4) {
+ // TiDB only allow utf8 to be changed to utf8mb4, or changing the collation when the charset is utf8/utf8mb4.
  return nil
  }