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ActiveAndroid fork with reactive extensions.
There is a newer version: 3.1.5
package com.activeandroid.rx;


import android.database.Cursor;
import android.text.TextUtils;

import com.activeandroid.Cache;
import com.activeandroid.Model;
import com.activeandroid.rxschedulers.AndroidSchedulers;
import com.activeandroid.sqlbrite.SqlBrite;
import com.activeandroid.util.SQLiteUtils;

import java.util.List;

import rx.functions.Func1;
import rx.schedulers.Schedulers;

/**
 * Created by Victor on 30/10/2015.
 */
public class RxSelect {

    private Class mType;
    private String mAlias;
    private String mWhere;
    private String mLimit;
    private String mGroupBy;
    private String mHaving;
    private String mOrderBy;
    private String mOffset;

    private RxSelect(Class type) {
        this.mType = type;
    }

    public static  RxSelect from(Class type) {
        return new RxSelect<>(type);
    }

    public RxSelect as(String alias) {
        mAlias = alias;
        return this;
    }

    public RxSelect groupBy(String groupBy) {
        mGroupBy = groupBy;
        return this;
    }

    public RxSelect where(String where) {
        this.mWhere = where;
        return this;
    }

    public RxSelect orderBy(String orderBy) {
        mOrderBy = orderBy;
        return this;
    }

    public RxSelect limit(int limit) {
        return limit(String.valueOf(limit));
    }

    public RxSelect limit(String limit) {
        mLimit = limit;
        return this;
    }

    public RxSelect offset(int offset) {
        return offset(String.valueOf(offset));
    }

    public RxSelect offset(String offset) {
        mOffset = offset;
        return this;
    }

    public RxSelect having(String having) {
        mHaving = having;
        return this;
    }

    public  rx.Observable> execute() {

        String sql = buildSql();

        return Cache.openDatabase().createQuery(Cache.getTableName(mType), sql)
                .subscribeOn(Schedulers.io())
                .map(new Func1>() {
                    @Override
                    public List call(SqlBrite.Query query) {
                        try {
                            Cursor cursor = query.run();
                            return SQLiteUtils.processCursor(mType, cursor);

                        } catch (Exception ex) {
                            ex.printStackTrace();
                        }

                        return null;

                    }
                })
                .observeOn(AndroidSchedulers.mainThread());
    }

    public rx.Observable executeSingle() {

        String sql = buildSql();

        return Cache.openDatabase().createQuery(Cache.getTableName(mType), sql)
                .subscribeOn(Schedulers.io())
                .map(new Func1() {
                    @Override
                    public T call(SqlBrite.Query query) {
                        try {
                            Cursor cursor = query.run();
                            if (cursor != null && cursor.getCount() > 0) {
                                cursor.moveToFirst();
                                Model model = (Model) mType.newInstance();
                                model.loadFromCursor(cursor);
                                return (T) model;
                            }
                        } catch (Exception ex) {
                            ex.printStackTrace();
                        }

                        return null;

                    }
                })
                .observeOn(AndroidSchedulers.mainThread());
    }

    private String buildSql() {
        StringBuilder sql = new StringBuilder();

        buildSelect(sql);
        addFrom(sql);
        addWhere(sql);
        addLimit(sql);

        return sql.toString();
    }

    private void buildSelect(final StringBuilder sql) {
        sql.append("SELECT * ");
    }

    private void addFrom(final StringBuilder sql) {
        sql.append("FROM ");
        sql.append(Cache.getTableName(mType)).append(" ");

        if (mAlias != null) {
            sql.append("AS ");
            sql.append(mAlias);
            sql.append(" ");
        }
    }

    private void addWhere(final StringBuilder sql) {
        if (!TextUtils.isEmpty(mWhere)) {
            sql.append("WHERE ");
            sql.append(mWhere);
            sql.append(" ");
        }
    }

    private void addGroupBy(final StringBuilder sql) {
        if (mGroupBy != null) {
            sql.append("GROUP BY ");
            sql.append(mGroupBy);
            sql.append(" ");
        }
    }

    private void addHaving(final StringBuilder sql) {
        if (mHaving != null) {
            sql.append("HAVING ");
            sql.append(mHaving);
            sql.append(" ");
        }
    }

    private void addOrderBy(final StringBuilder sql) {
        if (mOrderBy != null) {
            sql.append("ORDER BY ");
            sql.append(mOrderBy);
            sql.append(" ");
        }
    }

    private void addLimit(final StringBuilder sql) {
        if (!TextUtils.isEmpty(mLimit)) {
            sql.append("LIMIT ");
            sql.append(mLimit);
            sql.append(" ");
        }
    }

    private void addOffset(final StringBuilder sql) {
        if (mOffset != null) {
            sql.append("OFFSET ");
            sql.append(mOffset);
            sql.append(" ");
        }
    }
}