feat: migrator support to change table column

contracts/database/schema/column.go

@@ -3,6 +3,8 @@ package schema
 type ColumnDefinition interface {
 	// AutoIncrement set the column as auto increment
 	AutoIncrement() ColumnDefinition
+	// Change the column
+	Change() ColumnDefinition
 	// Comment sets the comment value
 	Comment(comment string) ColumnDefinition
 	// Default set the default value
@@ -37,6 +39,8 @@ type ColumnDefinition interface {
 	GetUseCurrent() bool
 	// GetUseCurrentOnUpdate returns the useCurrentOnUpdate value
 	GetUseCurrentOnUpdate() bool
+	// IsChange returns true if the column has changed
+	IsChange() bool
 	// IsSetComment returns true if the comment value is set
 	IsSetComment() bool
 	// OnUpdate sets the column to use the value on update (Mysql only)

contracts/database/schema/grammar.go

@@ -3,6 +3,8 @@ package schema
 type Grammar interface {
 	// CompileAdd Compile an add column command.
 	CompileAdd(blueprint Blueprint, command *Command) string
+	// CompileChange Compile a change column command.
+	CompileChange(blueprint Blueprint, command *Command) []string
 	// CompileColumns Compile the query to determine the columns.
 	CompileColumns(schema, table string) string
 	// CompileComment Compile a column comment command.

database/schema/blueprint.go

@@ -430,6 +430,12 @@ func (r *Blueprint) ToSql(grammar schema.Grammar) []string {
 
 		switch command.Name {
 		case constants.CommandAdd:
+			if command.Column.IsChange() {
+				if statement := grammar.CompileChange(r, command); statement != nil {
+					statements = append(statements, statement...)
+				}
+				continue
+			}
 			statements = append(statements, grammar.CompileAdd(r, command))
 		case constants.CommandComment:
 			if statement := grammar.CompileComment(r, command); statement != "" {

database/schema/blueprint_test.go

@@ -386,6 +386,15 @@ func (s *BlueprintTestSuite) TestToSql() {
 		} else {
 			s.Empty(s.blueprint.ToSql(grammar))
 		}
+
+		// Change column
+		s.SetupTest()
+		s.blueprint.String("name", 100).Change()
+		if driver == database.DriverPostgres {
+			s.Len(s.blueprint.ToSql(grammar), 1)
+		} else {
+			s.Empty(s.blueprint.ToSql(grammar))
+		}
 	}
 }
 
@@ -438,3 +447,15 @@ func (s *BlueprintTestSuite) TestUnsignedTinyInteger() {
 		unsigned: convert.Pointer(true),
 	})
 }
+
+func (s *BlueprintTestSuite) TestChange() {
+	column := "name"
+	customLength := 100
+	s.blueprint.String(column, customLength).Change()
+	s.Contains(s.blueprint.GetAddedColumns(), &ColumnDefinition{
+		length: &customLength,
+		name:   &column,
+		change: true,
+		ttype:  convert.Pointer("string"),
+	})
+}

database/schema/column.go

@@ -8,6 +8,7 @@ import (
 type ColumnDefinition struct {
 	allowed            []any
 	autoIncrement      *bool
+	change             bool
 	comment            *string
 	def                any
 	length             *int
@@ -29,6 +30,12 @@ func (r *ColumnDefinition) AutoIncrement() schema.ColumnDefinition {
 	return r
 }
 
+func (r *ColumnDefinition) Change() schema.ColumnDefinition {
+	r.change = true
+
+	return r
+}
+
 func (r *ColumnDefinition) Comment(comment string) schema.ColumnDefinition {
 	r.comment = &comment
 
@@ -149,6 +156,10 @@ func (r *ColumnDefinition) GetUseCurrentOnUpdate() bool {
 	return false
 }
 
+func (r *ColumnDefinition) IsChange() bool {
+	return r.change
+}
+
 func (r *ColumnDefinition) IsSetComment() bool {
 	return r != nil && r.comment != nil
 }

database/schema/column_test.go

@@ -63,6 +63,13 @@ func (s *ColumnDefinitionTestSuite) GetType() {
 	s.Equal("string", s.columnDefinition.GetType())
 }
 
+func (s *ColumnDefinitionTestSuite) IsChange() {
+	s.False(s.columnDefinition.IsChange())
+
+	s.columnDefinition.Change()
+	s.True(s.columnDefinition.IsChange())
+}
+
 func (s *ColumnDefinitionTestSuite) Unsigned() {
 	s.columnDefinition.Unsigned()
 	s.True(*s.columnDefinition.unsigned)

database/schema/grammars/mysql.go

@@ -41,6 +41,12 @@ func (r *Mysql) CompileAdd(blueprint schema.Blueprint, command *schema.Command)
 	return fmt.Sprintf("alter table %s add %s", r.wrap.Table(blueprint.GetTableName()), r.getColumn(blueprint, command.Column))
 }
 
+func (r *Mysql) CompileChange(blueprint schema.Blueprint, command *schema.Command) []string {
+	return []string{
+		fmt.Sprintf("alter table %s modify %s", r.wrap.Table(blueprint.GetTableName()), r.getColumn(blueprint, command.Column)),
+	}
+}
+
 func (r *Mysql) CompileColumns(schema, table string) string {
 	return fmt.Sprintf(
 		"select column_name as `name`, data_type as `type_name`, column_type as `type`, "+

database/schema/grammars/mysql_test.go

@@ -43,6 +43,27 @@ func (s *MysqlSuite) TestCompileAdd() {
 	s.Equal("alter table `goravel_users` add `name` varchar(1) not null default 'goravel' comment 'comment'", sql)
 }
 
+func (s *MysqlSuite) TestCompileChange() {
+	mockBlueprint := mocksschema.NewBlueprint(s.T())
+	mockColumn := mocksschema.NewColumnDefinition(s.T())
+
+	mockBlueprint.EXPECT().GetTableName().Return("users").Once()
+	mockColumn.EXPECT().GetName().Return("name").Once()
+	mockColumn.EXPECT().GetType().Return("string").Twice()
+	mockColumn.EXPECT().GetDefault().Return("goravel").Twice()
+	mockColumn.EXPECT().GetNullable().Return(false).Once()
+	mockColumn.EXPECT().GetLength().Return(1).Once()
+	mockColumn.EXPECT().GetOnUpdate().Return(nil).Once()
+	mockColumn.EXPECT().GetComment().Return("comment").Once()
+	mockColumn.EXPECT().GetUnsigned().Return(false).Once()
+
+	sql := s.grammar.CompileChange(mockBlueprint, &contractsschema.Command{
+		Column: mockColumn,
+	})
+
+	s.Equal([]string{"alter table `goravel_users` modify `name` varchar(1) not null default 'goravel' comment 'comment'"}, sql)
+}
+
 func (s *MysqlSuite) TestCompileCreate() {
 	mockColumn1 := mocksschema.NewColumnDefinition(s.T())
 	mockColumn2 := mocksschema.NewColumnDefinition(s.T())

database/schema/grammars/postgres.go

@@ -39,16 +39,29 @@
 	return fmt.Sprintf("alter table %s add column %s", r.wrap.Table(blueprint.GetTableName()), r.getColumn(blueprint, command.Column))
 }
 
+func (r *Postgres) CompileChange(blueprint schema.Blueprint, command *schema.Command) []string {
+	changes := []string{fmt.Sprintf("alter column %s type %s", r.wrap.Column(command.Column.GetName()), getType(r, command.Column))}
+	for _, modifier := range r.modifiers {
+		if change := modifier(blueprint, command.Column); change != "" {
+			changes = append(changes, fmt.Sprintf("alter column %s%s", r.wrap.Column(command.Column.GetName()), change))
+		}
+	}
+
+	return []string{
+		fmt.Sprintf("alter table %s %s", r.wrap.Table(blueprint.GetTableName()), strings.Join(changes, ", ")),
+	}
+}
+
 func (r *Postgres) CompileColumns(schema, table string) string {
 	return fmt.Sprintf(
 		"select a.attname as name, t.typname as type_name, format_type(a.atttypid, a.atttypmod) as type, "+
-			"(select tc.collcollate from pg_catalog.pg_collation tc where tc.oid = a.attcollation) as collation, "+
-			"not a.attnotnull as nullable, "+
-			"(select pg_get_expr(adbin, adrelid) from pg_attrdef where c.oid = pg_attrdef.adrelid and pg_attrdef.adnum = a.attnum) as default, "+
-			"col_description(c.oid, a.attnum) as comment "+
-			"from pg_attribute a, pg_class c, pg_type t, pg_namespace n "+
-			"where c.relname = %s and n.nspname = %s and a.attnum > 0 and a.attrelid = c.oid and a.atttypid = t.oid and n.oid = c.relnamespace "+
-			"order by a.attnum", r.wrap.Quote(table), r.wrap.Quote(schema))
+				"(select tc.collcollate from pg_catalog.pg_collation tc where tc.oid = a.attcollation) as collation, "+
+				"not a.attnotnull as nullable, "+
+				"(select pg_get_expr(adbin, adrelid) from pg_attrdef where c.oid = pg_attrdef.adrelid and pg_attrdef.adnum = a.attnum) as default, "+
+				"col_description(c.oid, a.attnum) as comment "+
+				"from pg_attribute a, pg_class c, pg_type t, pg_namespace n "+
+				"where c.relname = %s and n.nspname = %s and a.attnum > 0 and a.attrelid = c.oid and a.atttypid = t.oid and n.oid = c.relnamespace "+
+				"order by a.attnum", r.wrap.Quote(table), r.wrap.Quote(schema))
 }
 
 func (r *Postgres) CompileComment(blueprint schema.Blueprint, command *schema.Command) string {
@@ -194,16 +207,16 @@
 func (r *Postgres) CompileIndexes(schema, table string) string {
 	return fmt.Sprintf(
 		"select ic.relname as name, string_agg(a.attname, ',' order by indseq.ord) as columns, "+
-			"am.amname as \"type\", i.indisunique as \"unique\", i.indisprimary as \"primary\" "+
-			"from pg_index i "+
-			"join pg_class tc on tc.oid = i.indrelid "+
-			"join pg_namespace tn on tn.oid = tc.relnamespace "+
-			"join pg_class ic on ic.oid = i.indexrelid "+
-			"join pg_am am on am.oid = ic.relam "+
-			"join lateral unnest(i.indkey) with ordinality as indseq(num, ord) on true "+
-			"left join pg_attribute a on a.attrelid = i.indrelid and a.attnum = indseq.num "+
-			"where tc.relname = %s and tn.nspname = %s "+
-			"group by ic.relname, am.amname, i.indisunique, i.indisprimary",
+				"am.amname as \"type\", i.indisunique as \"unique\", i.indisprimary as \"primary\" "+
+				"from pg_index i "+
+				"join pg_class tc on tc.oid = i.indrelid "+
+				"join pg_namespace tn on tn.oid = tc.relnamespace "+
+				"join pg_class ic on ic.oid = i.indexrelid "+
+				"join pg_am am on am.oid = ic.relam "+
+				"join lateral unnest(i.indkey) with ordinality as indseq(num, ord) on true "+
+				"left join pg_attribute a on a.attrelid = i.indrelid and a.attnum = indseq.num "+
+				"where tc.relname = %s and tn.nspname = %s "+
+				"group by ic.relname, am.amname, i.indisunique, i.indisprimary",
 		r.wrap.Quote(table),
 		r.wrap.Quote(schema),
 	)
@@ -225,9 +238,9 @@
 
 func (r *Postgres) CompileTables(_ string) string {
 	return "select c.relname as name, n.nspname as schema, pg_total_relation_size(c.oid) as size, " +
-		"obj_description(c.oid, 'pg_class') as comment from pg_class c, pg_namespace n " +
-		"where c.relkind in ('r', 'p') and n.oid = c.relnamespace and n.nspname not in ('pg_catalog', 'information_schema') " +
-		"order by c.relname"
+			"obj_description(c.oid, 'pg_class') as comment from pg_class c, pg_namespace n " +
+			"where c.relkind in ('r', 'p') and n.oid = c.relnamespace and n.nspname not in ('pg_catalog', 'information_schema') " +
+			"order by c.relname"
 }
 
 func (r *Postgres) CompileTypes() string {
@@ -291,6 +304,15 @@
 }
 
 func (r *Postgres) ModifyDefault(blueprint schema.Blueprint, column schema.ColumnDefinition) string {
+	if column.IsChange() {
+		if column.GetAutoIncrement() {
+			return ""
+		}
+		if column.GetDefault() != nil {
+			return fmt.Sprintf(" set default %s", getDefaultValue(column.GetDefault()))
+		}
+		return " drop default"
+	}
 	if column.GetDefault() != nil {
 		return fmt.Sprintf(" default %s", getDefaultValue(column.GetDefault()))
 	}
@@ -299,15 +321,20 @@
 }
 
 func (r *Postgres) ModifyNullable(blueprint schema.Blueprint, column schema.ColumnDefinition) string {
+	if column.IsChange() {
+		if column.GetNullable() {
+			return " drop not null"
+		}
+		return " set not null"
+	}
 	if column.GetNullable() {
 		return " null"
-	} else {
-		return " not null"
 	}
+	return " not null"
 }
 
 func (r *Postgres) ModifyIncrement(blueprint schema.Blueprint, column schema.ColumnDefinition) string {
-	if !blueprint.HasCommand("primary") && slices.Contains(r.serials, column.GetType()) && column.GetAutoIncrement() {
+	if !column.IsChange() && !blueprint.HasCommand("primary") && slices.Contains(r.serials, column.GetType()) && column.GetAutoIncrement() {
 		return " primary key"
 	}