Create table with boolean type, the boolean column is treated as number instead of boolean

[shelly-li-sl]

When creating table with boolean type, the boolean type was converted to NUMBER(1) column in DB instead of BOOLEAN type.

For the following test

type BooleanBasicModel struct {
	ID        uint `gorm:"primaryKey;autoIncrement"`
	Flag      bool
	Nullable  sql.NullBool
	CreatedAt time.Time
	UpdatedAt time.Time
}

func setupBooleanTestTables(t *testing.T) {
	t.Log("Setting up Boolean test tables")
	_ = DB.Migrator().DropTable(&BooleanBasicModel{})

	if err := DB.AutoMigrate(&BooleanBasicModel{}); err != nil {
		t.Fatalf("Failed to migrate BooleanBasicModel: %v", err)
	}
}

func TestBooleanBasicInsert(t *testing.T) {
	setupBooleanTestTables(t)

	// Insert a TRUE record with non-null Nullable=true
	trueRecord := &BooleanBasicModel{
		Flag:     true,
		Nullable: sql.NullBool{Bool: true, Valid: true},
	}
	if err := DB.Create(trueRecord).Error; err != nil {
		t.Fatalf("Failed to insert TRUE record: %v", err)
	}
	if trueRecord.ID == 0 {
		t.Fatal("Expected auto-generated ID for TRUE record")
	}

}

The generated create table and insert SQLs are:

2025/10/28 22:59:43 /scratch/shulili/GORM/gorm-github/gorm-oracle/oracle/migrator.go:208
[13.729ms] [rows:0] CREATE TABLE "boolean_basic_models" ("id" NUMBER(20) GENERATED BY DEFAULT AS IDENTITY,"flag" NUMBER(1),"nullable" NUMBER(1),"created_at" TIMESTAMP WITH TIME ZONE,"updated_at" TIMESTAMP WITH TIME ZONE,PRIMARY KEY ("id"))

2025/10/28 22:59:43 /scratch/shulili/GORM/gorm-github/gorm-oracle/tests/boolean_test.go:35
[5.443ms] [rows:1] INSERT INTO "boolean_basic_models" ("flag","nullable","created_at","updated_at") VALUES (1,true,'2025-10-28 22:59:43.369','2025-10-28 22:59:43.369') RETURNING "id" INTO 1

The boolean type columns are created as NUMBER column in the database. I think it should create BOOLEAN columns as well because BOOLEAN type is supported in 23.26. So the generated SQLs should be:

CREATE TABLE "boolean_basic_models" ("id" NUMBER(20) GENERATED BY DEFAULT AS IDENTITY,"flag" BOOLEAN,"nullable" BOOLEAN,"created_at" TIMESTAMP WITH TIME ZONE,"updated_at" TIMESTAMP WITH TIME ZONE,PRIMARY KEY ("id"))

INSERT INTO "boolean_basic_models" ("flag","nullable","created_at","updated_at") VALUES (true,true,'2025-10-28 22:59:43.369','2025-10-28 22:59:43.369') RETURNING "id" INTO 1

The above SQLs could work well in 23.26 using sqlplus:

$ sqlplus scott/tiger@inst1

SQL*Plus: Release 23.26.1.0.0 - for Oracle Cloud and Engineered Systems on Tue Oct 28 23:07:57 2025
Version 23.26.1.0.0

Copyright (c) 1982, 2025, Oracle.  All rights reserved.

Last Successful login time: Tue Oct 28 2025 22:59:42 +00:00

Connected to:
Oracle AI Database 26ai Enterprise Edition Release 23.26.1.0.0 - for Oracle Cloud and Engineered Systems
Version 23.26.1.0.0

SQL> CREATE TABLE "boolean_basic_models" ("id" NUMBER(20) GENERATED BY DEFAULT AS IDENTITY,"flag" BOOLEAN,"nullable" BOOLEAN,"created_at" TIMESTAMP WITH TIME ZONE,"updated_at" TIMESTAMP WITH TIME ZONE,PRIMARY KEY ("id"));

Table created.

SQL> INSERT INTO "boolean_basic_models" ("flag","nullable") VALUES (true,true);

1 row created.

SQL> desc "boolean_basic_models";
 Name                                      Null?    Type
 ----------------------------------------- -------- ----------------------------
 id                                        NOT NULL NUMBER(20)
 flag                                               BOOLEAN
 nullable                                           BOOLEAN
 created_at                                         TIMESTAMP(6) WITH TIME ZONE
 updated_at                                         TIMESTAMP(6) WITH TIME ZONE


SQL> select * from "boolean_basic_models";

        id flag       nullable   created_at updated_at
---------- ---------- ---------- ---------- ----------
         1 TRUE       TRUE

SQL>