diff --git a/src/operations/tables.ts b/src/operations/tables.ts
index df153033..72842532 100644
--- a/src/operations/tables.ts
+++ b/src/operations/tables.ts
@@ -481,7 +481,7 @@ export function dropColumns(mOptions: MigrationOptions): DropColumns {
 
     const columnsStr = formatLines(
       columns.map(mOptions.literal),
-      `  DROP ${ifExists ? ' IF EXISTS' : ''}`,
+      `  DROP ${ifExists ? 'IF EXISTS ' : ''}`,
       `${cascade ? ' CASCADE' : ''},`
     );
 
diff --git a/test/operations/columns/addColumns.spec.ts b/test/operations/columns/addColumns.spec.ts
new file mode 100644
index 00000000..e6025da1
--- /dev/null
+++ b/test/operations/columns/addColumns.spec.ts
@@ -0,0 +1,87 @@
+import { describe, expect, it } from 'vitest';
+import { PgType } from '../../../src';
+import { addColumns } from '../../../src/operations/tables';
+import { options1 } from '../../utils';
+
+describe('operations', () => {
+  describe('columns', () => {
+    describe('addColumns', () => {
+      const addColumnsFn = addColumns(options1);
+
+      it('should return a function', () => {
+        expect(addColumnsFn).toBeTypeOf('function');
+      });
+
+      it('should return sql statement', () => {
+        const statement = addColumnsFn('transactions', {
+          status: {
+            type: 'varchar(30)',
+            default: 'old',
+          },
+          mtime: {
+            type: PgType.TIMESTAMP_WITH_TIME_ZONE,
+            default: 'now()',
+          },
+        });
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toBe(`ALTER TABLE "transactions"
+  ADD "status" varchar(30) DEFAULT $pga$old$pga$,
+  ADD "mtime" timestamp with time zone DEFAULT $pga$now()$pga$;`);
+      });
+
+      it('should return sql statement with columnOptions', () => {
+        const statement = addColumnsFn(
+          'transactions',
+          {
+            status: {
+              type: 'varchar(30)',
+              default: 'old',
+            },
+          },
+          {
+            ifNotExists: true,
+          }
+        );
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toBe(`ALTER TABLE "transactions"
+  ADD IF NOT EXISTS "status" varchar(30) DEFAULT $pga$old$pga$;`);
+      });
+
+      it('should return sql statement with schema', () => {
+        const statement = addColumnsFn(
+          { schema: 'myschema', name: 'distributors' },
+          {
+            status: PgType.VARCHAR,
+          }
+        );
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toBe(
+          `ALTER TABLE "myschema"."distributors"
+  ADD "status" varchar;`
+        );
+      });
+
+      describe('reverse', () => {
+        it('should contain a reverse function', () => {
+          expect(addColumnsFn.reverse).toBeTypeOf('function');
+        });
+
+        it('should return sql statement', () => {
+          const statement = addColumnsFn.reverse('transactions', {
+            status: {
+              type: 'varchar(30)',
+              default: 'old',
+            },
+          });
+
+          expect(statement).toBeTypeOf('string');
+          expect(statement).toBe(`ALTER TABLE "transactions"
+  DROP "status";`);
+        });
+      });
+    });
+  });
+});
diff --git a/test/operations/columns/alterColumn.spec.ts b/test/operations/columns/alterColumn.spec.ts
new file mode 100644
index 00000000..2d53f2fe
--- /dev/null
+++ b/test/operations/columns/alterColumn.spec.ts
@@ -0,0 +1,44 @@
+import { describe, expect, it } from 'vitest';
+import { alterColumn } from '../../../src/operations/tables';
+import { options1 } from '../../utils';
+
+describe('operations', () => {
+  describe('columns', () => {
+    describe('alterColumn', () => {
+      const alterColumnFn = alterColumn(options1);
+
+      it('should return a function', () => {
+        expect(alterColumnFn).toBeTypeOf('function');
+      });
+
+      it('should return sql statement', () => {
+        const statement = alterColumnFn('distributors', 'address', {});
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toHaveLength(0);
+      });
+
+      it('should return sql statement with columnOptions', () => {
+        const statement = alterColumnFn('distributors', 'address', {
+          default: null,
+          type: 'varchar(30)',
+          collation: 'C',
+          using: 'address::text',
+          notNull: false,
+          sequenceGenerated: null,
+          comment: 'Address of the distributor',
+        });
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toStrictEqual(
+          `ALTER TABLE "distributors"
+  ALTER "address" DROP DEFAULT,
+  ALTER "address" SET DATA TYPE varchar(30) COLLATE C USING address::text,
+  ALTER "address" DROP NOT NULL,
+  ALTER "address" DROP IDENTITY;
+COMMENT ON COLUMN "distributors"."address" IS $pga$Address of the distributor$pga$;`
+        );
+      });
+    });
+  });
+});
diff --git a/test/operations/columns/dropColumns.spec.ts b/test/operations/columns/dropColumns.spec.ts
new file mode 100644
index 00000000..09eb6d7e
--- /dev/null
+++ b/test/operations/columns/dropColumns.spec.ts
@@ -0,0 +1,58 @@
+import { describe, expect, it } from 'vitest';
+import { dropColumns } from '../../../src/operations/tables';
+import { options1 } from '../../utils';
+
+describe('operations', () => {
+  describe('columns', () => {
+    describe('dropColumns', () => {
+      const dropColumnsFn = dropColumns(options1);
+
+      it('should return a function', () => {
+        expect(dropColumnsFn).toBeTypeOf('function');
+      });
+
+      it('should return sql statement', () => {
+        const statement = dropColumnsFn('distributors', 'address');
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toBe(
+          `ALTER TABLE "distributors"
+  DROP "address";`
+        );
+      });
+
+      it('should return sql statement with dropOptions', () => {
+        const statement = dropColumnsFn(
+          'distributors',
+          {
+            address: 'varchar(30)',
+          },
+          {
+            ifExists: true,
+            cascade: true,
+          }
+        );
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toBe(`ALTER TABLE "distributors"
+  DROP IF EXISTS "address";`);
+      });
+
+      it('should return sql statement with schema', () => {
+        const statement = dropColumnsFn(
+          {
+            schema: 'myschema',
+            name: 'distributors',
+          },
+          {
+            address: 'varchar(30)',
+          }
+        );
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toBe(`ALTER TABLE "myschema"."distributors"
+  DROP "address";`);
+      });
+    });
+  });
+});
diff --git a/test/operations/columns/renameColumn.spec.ts b/test/operations/columns/renameColumn.spec.ts
new file mode 100644
index 00000000..d59c1ee7
--- /dev/null
+++ b/test/operations/columns/renameColumn.spec.ts
@@ -0,0 +1,56 @@
+import { describe, expect, it } from 'vitest';
+import { renameColumn } from '../../../src/operations/tables';
+import { options1 } from '../../utils';
+
+describe('operations', () => {
+  describe('columns', () => {
+    describe('renameColumn', () => {
+      const renameColumnFn = renameColumn(options1);
+
+      it('should return a function', () => {
+        expect(renameColumnFn).toBeTypeOf('function');
+      });
+
+      it('should return sql statement', () => {
+        const statement = renameColumnFn('distributors', 'address', 'city');
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toStrictEqual(
+          'ALTER TABLE "distributors" RENAME "address" TO "city";'
+        );
+      });
+
+      it('should return sql statement with schema', () => {
+        const statement = renameColumnFn(
+          { name: 'distributors', schema: 'myschema' },
+          'address',
+          'city'
+        );
+
+        expect(statement).toBeTypeOf('string');
+        expect(statement).toStrictEqual(
+          'ALTER TABLE "myschema"."distributors" RENAME "address" TO "city";'
+        );
+      });
+
+      describe('reverse', () => {
+        it('should contain a reverse function', () => {
+          expect(renameColumnFn.reverse).toBeTypeOf('function');
+        });
+
+        it('should return sql statement', () => {
+          const statement = renameColumnFn.reverse(
+            'distributors',
+            'address',
+            'city'
+          );
+
+          expect(statement).toBeTypeOf('string');
+          expect(statement).toBe(
+            'ALTER TABLE "distributors" RENAME "city" TO "address";'
+          );
+        });
+      });
+    });
+  });
+});