diff --git a/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn b/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn
index 048458b55c76..dcfb766957f7 100644
--- a/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn
+++ b/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn
@@ -520,7 +520,7 @@ CREATE TABLE shopping (item, quantity) AS VALUES ('cups', 10), ('plates', 30), (
 statement count 3
 SELECT * FROM shopping
 
-statement error pgcode 42P15 division by zero
+statement error pgcode 22012 division by zero
 ALTER TABLE shopping ADD COLUMN c int AS (quantity::int // 0) STORED
 
 statement ok
@@ -1746,3 +1746,28 @@ DROP TABLE people;
 
 statement ok
 COMMIT;
+
+subtest add_column_default_sequence_op
+
+# This is a current known limitation (#42508). This test ensures that
+# the error message is properly reported, with issue hint.
+# Once the limitation is lifted, this entire test can be removed
+# (and replaced by test for the feature).
+
+statement ok
+CREATE TABLE t42508(x INT); INSERT INTO t42508(x) VALUES (1);
+
+statement ok
+CREATE SEQUENCE s42508
+
+statement error pgcode 0A000 unimplemented: cannot backfill such sequence operation.*\nHINT.*\n.*42508
+ALTER TABLE t42508 ADD COLUMN y INT DEFAULT nextval('s42508')
+
+statement ok
+BEGIN
+
+statement ok
+ALTER TABLE t42508 ADD COLUMN y INT DEFAULT nextval('s42508')
+
+statement error pgcode XXA00 unimplemented: cannot backfill such sequence operation.*\nHINT.*\n.*42508
+COMMIT
diff --git a/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn-mixed-19.1-19.2 b/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn-mixed-19.1-19.2
index d9b78f36bcd1..da68e12382ba 100644
--- a/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn-mixed-19.1-19.2
+++ b/pkg/sql/logictest/testdata/logic_test/schema_change_in_txn-mixed-19.1-19.2
@@ -495,7 +495,7 @@ CREATE TABLE shopping (item, quantity) AS VALUES ('cups', 10), ('plates', 30), (
 statement count 3
 SELECT * FROM shopping
 
-statement error pgcode 42P15 division by zero
+statement error pgcode 22012 division by zero
 ALTER TABLE shopping ADD COLUMN c int AS (quantity::int // 0) STORED
 
 statement ok
@@ -1340,3 +1340,28 @@ COMMIT
 
 statement ok
 DROP TABLE t
+
+subtest add_column_default_sequence_op
+
+# This is a current known limitation (#42508). This test ensures that
+# the error message is properly reported, with issue hint.
+# Once the limitation is lifted, this entire test can be removed
+# (and replaced by test for the feature).
+
+statement ok
+CREATE TABLE t42508(x INT); INSERT INTO t42508(x) VALUES (1);
+
+statement ok
+CREATE SEQUENCE s42508
+
+statement error pgcode 0A000 unimplemented: cannot backfill such sequence operation.*\nHINT.*\n.*42508
+ALTER TABLE t42508 ADD COLUMN y INT DEFAULT nextval('s42508')
+
+statement ok
+BEGIN
+
+statement ok
+ALTER TABLE t42508 ADD COLUMN y INT DEFAULT nextval('s42508')
+
+statement error pgcode XXA00 unimplemented: cannot backfill such sequence operation.*\nHINT.*\n.*42508
+COMMIT
diff --git a/pkg/sql/sqlbase/errors.go b/pkg/sql/sqlbase/errors.go
index 4ccbdd26009c..7829ee22c351 100644
--- a/pkg/sql/sqlbase/errors.go
+++ b/pkg/sql/sqlbase/errors.go
@@ -49,7 +49,7 @@ func NewNonNullViolationError(columnName string) error {
 // NewInvalidSchemaDefinitionError creates an error for an invalid schema
 // definition such as a schema definition that doesn't parse.
 func NewInvalidSchemaDefinitionError(err error) error {
-	return pgerror.New(pgcode.InvalidSchemaDefinition, err.Error())
+	return pgerror.WithCandidateCode(err, pgcode.InvalidSchemaDefinition)
 }
 
 // NewUnsupportedSchemaUsageError creates an error for an invalid
diff --git a/pkg/sql/sqlbase/evalctx.go b/pkg/sql/sqlbase/evalctx.go
index d892aae215db..6ac61297e5dc 100644
--- a/pkg/sql/sqlbase/evalctx.go
+++ b/pkg/sql/sqlbase/evalctx.go
@@ -15,7 +15,8 @@ import (
 
 	"github.com/cockroachdb/cockroach/pkg/sql/sem/tree"
 	"github.com/cockroachdb/cockroach/pkg/sql/types"
-	"github.com/pkg/errors"
+	"github.com/cockroachdb/cockroach/pkg/util/errorutil/unimplemented"
+	"github.com/cockroachdb/errors"
 )
 
 // DummySequenceOperators implements the tree.SequenceOperators interface by
@@ -24,7 +25,7 @@ type DummySequenceOperators struct{}
 
 var _ tree.EvalDatabase = &DummySequenceOperators{}
 
-var errSequenceOperators = errors.New("cannot backfill such sequence operation")
+var errSequenceOperators = unimplemented.NewWithIssue(42508, "cannot backfill such sequence operation")
 
 // ParseQualifiedTableName is part of the tree.EvalDatabase interface.
 func (so *DummySequenceOperators) ParseQualifiedTableName(