ddl: fix rename index for expression indexes (#51984)

ddl/column.go

@@ -2041,3 +2041,12 @@
 	}
 	return columnName[:pos]
 }
+
+func getExpressionIndexOriginName(expressionIdx *model.ColumnInfo) string {
+	columnName := strings.TrimPrefix(expressionIdx.Name.O, expressionIndexPrefix+"_")
+	var pos int
+	if pos = strings.LastIndex(columnName, "_"); pos == -1 {
+		return columnName
+	}
+	return columnName[:pos]
+}

ddl/index.go

@@ -392,6 +392,8 @@
 	}
 
 	renameIndexes(tblInfo, from, to)
+	renameHiddenColumns(tblInfo, from, to)
+
 	if ver, err = updateVersionAndTableInfo(d, t, job, tblInfo, true); err != nil {
 		job.State = model.JobStateCancelled
 		return ver, errors.Trace(err)
@@ -2284,3 +2286,12 @@
 		}
 	}
 }
+
+func renameHiddenColumns(tblInfo *model.TableInfo, from, to model.CIStr) {
+	for _, col := range tblInfo.Columns {
+		if col.Hidden && getExpressionIndexOriginName(col) == from.O {
+			col.Name.L = strings.Replace(col.Name.L, from.L, to.L, 1)
+			col.Name.O = strings.Replace(col.Name.O, from.O, to.O, 1)
+		}
+	}
+}

tests/integrationtest/r/ddl/db_rename.result

@@ -0,0 +1,27 @@
+drop table if exists t;
+create table t (pk int primary key, c int default 1, c1 int default 1, unique key k1(c), key k2(c1));
+alter table t rename index k1 to k3;
+admin check index t k3;
+alter table t rename index k3 to k3;
+admin check index t k3;
+alter table t rename index x to x;
+Error 1176 (42000): Key 'x' doesn't exist in table 't'
+alter table t rename index k3 to k2;
+Error 1061 (42000): Duplicate key name 'k2'
+alter table t rename index k2 to K2;
+alter table t rename key k3 to K2;
+Error 1061 (42000): Duplicate key name 'K2'
+drop table t;
+create table t(j json);
+alter table t add index idx1((cast(j as char(10) array)));
+alter table t rename index idx1 to idx2;
+alter table t add index idx1((cast(j as char(10) array)));
+insert into t values ('["1"]');
+alter table t add index IDX3((cast(j as char(10) array)));
+alter table t rename index IDX3 to IDX4;
+alter table t add index IDX3((cast(j as char(10) array)));
+insert into t values ('["2"]');
+select * from t;
+j
+["1"]
+["2"]

tests/integrationtest/t/ddl/db_rename.test

@@ -0,0 +1,27 @@
+# TestRenameIndex
+drop table if exists t;
+create table t (pk int primary key, c int default 1, c1 int default 1, unique key k1(c), key k2(c1));
+alter table t rename index k1 to k3;
+admin check index t k3;
+alter table t rename index k3 to k3;
+admin check index t k3;
+-- error 1176
+alter table t rename index x to x;
+-- error 1061
+alter table t rename index k3 to k2;
+alter table t rename index k2 to K2;
+-- error 1061
+alter table t rename key k3 to K2;
+
+# TestIssue51431
+drop table t;
+create table t(j json);
+alter table t add index idx1((cast(j as char(10) array)));
+alter table t rename index idx1 to idx2;
+alter table t add index idx1((cast(j as char(10) array)));
+insert into t values ('["1"]');
+alter table t add index IDX3((cast(j as char(10) array)));
+alter table t rename index IDX3 to IDX4;
+alter table t add index IDX3((cast(j as char(10) array)));
+insert into t values ('["2"]');
+select * from t;