# JoinQuery

> Construct join-query and use it in condition.

# JoinQuery

Construct join-query and use it in condition.

```apex
SOQL.of(Account.SObjectType)
    .whereAre(SOQL.Filter.with(Account.Id).isIn(
        SOQL.InnerJoin.of(Contact.SObjectType)
            .with(Contact.AccountId)
    )).toList();
```

## Methods

The following are methods for `FilterGroup`.

[**INIT**](#init)

- [`of(SObjectType ofObject)`](#of)

[**SELECT**](#select)

- [`with(SObjectField field)`](#with)

[**WHERE**](#where)

- [`whereAre(FilterGroup filterGroup)`](#whereare)
- [`whereAre(Filter filter)`](#whereare)

## INIT
### of

Constructs a `JoinQuery`.

**Signature**

```apex
static JoinQuery of(SObjectType ofObject)
```

**Example**

```sql
SELECT Id
FROM Account
WHERE Id IN (
    SELECT AccountId
    FROM Contact
    WHERE Name = 'My Contact'
)
```
```apex
SOQL.of(Account.SObjectType)
    .whereAre(SOQL.Filter.with(Account.Id).isIn(
        SOQL.InnerJoin.of(Contact.SObjectType)
            .with(Contact.AccountId)
    )).toList();
```

## SELECT
### with

> `SELECT` statement that specifies the fields to query.

**Signature**

```apex
static JoinQuery with(SObjectField field)
```

**Example**

```sql
SELECT Id
FROM Account
WHERE Id IN (
    SELECT AccountId
    FROM Contact
)
```
```apex
SOQL.of(Account.SObjectType)
    .whereAre(SOQL.Filter.with(Account.Id).isIn(
        SOQL.InnerJoin.of(Contact.SObjectType)
            .with(Contact.AccountId)
    )).toList();
```

## WHERE
### whereAre

> The condition expression in a `WHERE` clause of a SOQL query includes one or more field expressions. You can specify multiple field expressions in a condition expression by using logical operators.

For more details check [`SOQL.FilterGroup`](soql-filters-group.md) and [`SOQL.Filter`](soql-filter.md)

**Signature**

```apex
static JoinQuery whereAre(FilterGroup conditions)
```

**Example**

```sql
SELECT Id
FROM Account
WHERE Id IN (
    SELECT AccountId
    FROM Contact
    WHERE Name = 'My Contact'
)
```
```apex
SOQL.of(Account.SObjectType)
    .whereAre(SOQL.Filter.with(Account.Id).isIn(
        SOQL.InnerJoin.of(Contact.SObjectType)
            .with(Contact.AccountId)
            .whereAre(SOQL.Filter.with(Contact.Name).equal('My Contact'))
    )).toList();
```