cond_exists.go

@@ -0,0 +1,49 @@
+// Copyright 2022 The Xorm Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package builder
+
+import (
+	"errors"
+	"io"
+)
+
+type condExists struct {
+	subQuery *Builder
+}
+
+var _ Cond = condExists{}
+
+// Exists returns Cond via condition
+func Exists(subQuery *Builder) Cond {
+	return &condExists{
+		subQuery: subQuery,
+	}
+}
+
+func (condExists condExists) WriteTo(w Writer) error {
+	if !condExists.IsValid() {
+		return errors.New("exists condition is nov valid")
+	}
+	if _, err := io.WriteString(w, "EXISTS ("); err != nil {
+		return err
+	}
+	if err := condExists.subQuery.WriteTo(w); err != nil {
+		return err
+	}
+	_, err := io.WriteString(w, ")")
+	return err
+}
+
+func (condExists condExists) And(conds ...Cond) Cond {
+	return And(condExists, And(conds...))
+}
+
+func (condExists condExists) Or(conds ...Cond) Cond {
+	return Or(condExists, Or(conds...))
+}
+
+func (condExists condExists) IsValid() bool {
+	return condExists.subQuery != nil
+}

cond_exists_test.go

@@ -0,0 +1,32 @@
+// Copyright 2022 The Xorm Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package builder
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestExists(t *testing.T) {
+	cond1 := Exists(Select("*").From("table").Where(Eq{"col1": 1}))
+	sql, err := ToBoundSQL(cond1)
+	assert.NoError(t, err)
+	assert.EqualValues(t, "EXISTS (SELECT * FROM table WHERE col1=1)", sql)
+}
+
+func TestNotExists1(t *testing.T) {
+	cond1 := Exists(Select("*").From("table").Where(Eq{"col1": 1}))
+	sql, err := ToBoundSQL(Not{cond1})
+	assert.NoError(t, err)
+	assert.EqualValues(t, "NOT EXISTS (SELECT * FROM table WHERE col1=1)", sql)
+}
+
+func TestNotExists2(t *testing.T) {
+	cond1 := NotExists(Select("*").From("table").Where(Eq{"col1": 1}))
+	sql, err := ToBoundSQL(cond1)
+	assert.NoError(t, err)
+	assert.EqualValues(t, "NOT EXISTS (SELECT * FROM table WHERE col1=1)", sql)
+}

cond_not_exists.go

@@ -0,0 +1,49 @@
+// Copyright 2022 The Xorm Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package builder
+
+import (
+	"errors"
+	"io"
+)
+
+type condNotExists struct {
+	subQuery *Builder
+}
+
+var _ Cond = condNotExists{}
+
+// NotExists returns Cond via condition
+func NotExists(subQuery *Builder) Cond {
+	return &condNotExists{
+		subQuery: subQuery,
+	}
+}
+
+func (condNotExists condNotExists) WriteTo(w Writer) error {
+	if !condNotExists.IsValid() {
+		return errors.New("exists condition is nov valid")
+	}
+	if _, err := io.WriteString(w, "NOT EXISTS ("); err != nil {
+		return err
+	}
+	if err := condNotExists.subQuery.WriteTo(w); err != nil {
+		return err
+	}
+	_, err := io.WriteString(w, ")")
+	return err
+}
+
+func (condNotExists condNotExists) And(conds ...Cond) Cond {
+	return And(condNotExists, And(conds...))
+}
+
+func (condNotExists condNotExists) Or(conds ...Cond) Cond {
+	return Or(condNotExists, Or(conds...))
+}
+
+func (condNotExists condNotExists) IsValid() bool {
+	return condNotExists.subQuery != nil
+}