database/tidb
2
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

ddl: do change column data when binary to binary with different length (#24681)

Browse Source
This commit is contained in:
Lenshood
2021-07-22 16:06:13 +08:00
committed by GitHub
parent 39a4827fab
commit 11bc9c139d
3 changed files with 65 additions and 9 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
ddl/column.go
View File

@ -691,10 +691,10 @@ func needChangeColumnData(oldCol, newCol *model.ColumnInfo) bool {
return (newCol.Flen > 0 && newCol.Flen < oldCol.Flen) || (toUnsigned != originUnsigned)
}
// Ignore the potential max display length represented by integer's flen, use default flen instead.
oldColFlen, _ := mysql.GetDefaultFieldLengthAndDecimal(oldCol.Tp)
newColFlen, _ := mysql.GetDefaultFieldLengthAndDecimal(newCol.Tp)
defaultOldColFlen, _ := mysql.GetDefaultFieldLengthAndDecimal(oldCol.Tp)
defaultNewColFlen, _ := mysql.GetDefaultFieldLengthAndDecimal(newCol.Tp)
needTruncationOrToggleSignForInteger := func() bool {
return (newColFlen > 0 && newColFlen < oldColFlen) || (toUnsigned != originUnsigned)
return (defaultNewColFlen > 0 && defaultNewColFlen < defaultOldColFlen) || (toUnsigned != originUnsigned)
}
// Deal with the same type.
@ -708,6 +708,11 @@ func needChangeColumnData(oldCol, newCol *model.ColumnInfo) bool {
return isElemsChangedToModifyColumn(oldCol.Elems, newCol.Elems)
case mysql.TypeTiny, mysql.TypeShort, mysql.TypeInt24, mysql.TypeLong, mysql.TypeLonglong:
return toUnsigned != originUnsigned
case mysql.TypeString:
// Due to the behavior of padding \x00 at binary type, always change column data when binary length changed
if types.IsBinaryStr(&oldCol.FieldType) {
return newCol.Flen != oldCol.Flen
}
}
return needTruncationOrToggleSign()

51
ddl/db_test.go
View File

@ -4060,7 +4060,7 @@ func (s *testDBSuite5) TestModifyColumnRollBack(c *C) {
s.mustExec(tk, c, "drop table t1")
}
func (s *testSerialDBSuite) TestModifyColumnnReorgInfo(c *C) {
func (s *testSerialDBSuite) TestModifyColumnReorgInfo(c *C) {
tk := testkit.NewTestKit(c, s.store)
tk.MustExec("use test_db")
tk.MustExec("drop table if exists t1")
@ -4210,15 +4210,58 @@ func (s *testSerialDBSuite) TestModifyColumnBetweenStringTypes(c *C) {
tk.MustExec("create table tt (a varchar(10));")
tk.MustExec("insert into tt values ('111'),('10000');")
tk.MustExec("alter table tt change a a varchar(5);")
c2 := getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c.Assert(c2.FieldType.Flen, Equals, 5)
mvc := getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c.Assert(mvc.FieldType.Flen, Equals, 5)
tk.MustQuery("select * from tt").Check(testkit.Rows("111", "10000"))
tk.MustGetErrMsg("alter table tt change a a varchar(4);", "[types:1406]Data Too Long, field len 4, data len 5")
tk.MustExec("alter table tt change a a varchar(100);")
tk.MustQuery("select length(a) from tt").Check(testkit.Rows("3", "5"))
// char to char
tk.MustExec("drop table if exists tt;")
tk.MustExec("create table tt (a char(10));")
tk.MustExec("insert into tt values ('111'),('10000');")
tk.MustExec("alter table tt change a a char(5);")
mc := getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c.Assert(mc.FieldType.Flen, Equals, 5)
tk.MustQuery("select * from tt").Check(testkit.Rows("111", "10000"))
tk.MustGetErrMsg("alter table tt change a a char(4);", "[types:1406]Data Too Long, field len 4, data len 5")
tk.MustExec("alter table tt change a a char(100);")
tk.MustQuery("select length(a) from tt").Check(testkit.Rows("3", "5"))
// binary to binary
tk.MustExec("drop table if exists tt;")
tk.MustExec("create table tt (a binary(10));")
tk.MustExec("insert into tt values ('111'),('10000');")
tk.MustGetErrMsg("alter table tt change a a binary(5);", "[types:1406]Data Too Long, field len 5, data len 10")
mb := getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c.Assert(mb.FieldType.Flen, Equals, 10)
tk.MustQuery("select * from tt").Check(testkit.Rows("111\x00\x00\x00\x00\x00\x00\x00", "10000\x00\x00\x00\x00\x00"))
tk.MustGetErrMsg("alter table tt change a a binary(4);", "[types:1406]Data Too Long, field len 4, data len 10")
tk.MustExec("alter table tt change a a binary(12);")
tk.MustQuery("select * from tt").Check(testkit.Rows("111\x00\x00\x00\x00\x00\x00\x00\x00\x00", "10000\x00\x00\x00\x00\x00\x00\x00"))
tk.MustQuery("select length(a) from tt").Check(testkit.Rows("12", "12"))
// varbinary to varbinary
tk.MustExec("drop table if exists tt;")
tk.MustExec("create table tt (a varbinary(10));")
tk.MustExec("insert into tt values ('111'),('10000');")
tk.MustExec("alter table tt change a a varbinary(5);")
mvb := getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c.Assert(mvb.FieldType.Flen, Equals, 5)
tk.MustQuery("select * from tt").Check(testkit.Rows("111", "10000"))
tk.MustGetErrMsg("alter table tt change a a varbinary(4);", "[types:1406]Data Too Long, field len 4, data len 5")
tk.MustExec("alter table tt change a a varbinary(12);")
tk.MustQuery("select * from tt").Check(testkit.Rows("111", "10000"))
tk.MustQuery("select length(a) from tt").Check(testkit.Rows("3", "5"))
// varchar to char
tk.MustExec("drop table if exists tt;")
tk.MustExec("create table tt (a varchar(10));")
tk.MustExec("insert into tt values ('111'),('10000');")
tk.MustExec("alter table tt change a a char(10);")
c2 = getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c2 := getModifyColumn(c, s.s.(sessionctx.Context), "test", "tt", "a", false)
c.Assert(c2.FieldType.Tp, Equals, mysql.TypeString)
c.Assert(c2.FieldType.Flen, Equals, 10)
tk.MustQuery("select * from tt").Check(testkit.Rows("111", "10000"))

12
ddl/ddl_api.go
View File

@ -3575,8 +3575,16 @@ func needReorgToChange(origin *types.FieldType, to *types.FieldType) (needReorg
return true, "conversion between char and varchar string needs reorganization"
}
if toFlen > 0 && toFlen < originFlen {
return true, fmt.Sprintf("length %d is less than origin %d", toFlen, originFlen)
if toFlen > 0 && toFlen != originFlen {
if toFlen < originFlen {
return true, fmt.Sprintf("length %d is less than origin %d", toFlen, originFlen)
}
// Due to the behavior of padding \x00 at binary type, we need to reorg when binary length changed
isBinaryType := func(tp *types.FieldType) bool { return tp.Tp == mysql.TypeString && types.IsBinaryStr(tp) }
if isBinaryType(origin) && isBinaryType(to) {
return true, "can't change binary types of different length"
}
}
if to.Decimal > 0 && to.Decimal < origin.Decimal {
return true, fmt.Sprintf("decimal %d is less than origin %d", to.Decimal, origin.Decimal)