How many female users were surveyed in the mental health survey for 2017 in the state of Nebraska?
AnswerText = 'Yes' where questiontext = 'Do you have a family history of mental illness?'; AnswerText = 'Female' where questionid = 2; AnswerText = 'Nebraska' where questionid = 4
SELECT COUNT(*) FROM ( SELECT T2.UserID FROM Question AS T1 INNER JOIN Answer AS T2 ON T1.questionid = T2.QuestionID INNER JOIN Survey AS T3 ON T2.SurveyID = T3.SurveyID WHERE T3.Description = 'mental health survey for 2017' AND T1.questionid = 2 AND T2.AnswerText = 'Female' UNION SELECT T2.UserID FROM Question AS T1 INNER JOIN Answer AS T2 ON T1.questionid = T2.QuestionID INNER JOIN Survey AS T3 ON T2.SurveyID = T3.SurveyID WHERE T1.questionid = 4 AND T2.AnswerText = 'Nebraska' AND T3.Description = 'mental health survey for 2017' )
CREATE TABLE Question
(
    questiontext TEXT,
    questionid   INTEGER
        constraint Question_pk
            primary key
);
CREATE TABLE Survey
(
    SurveyID    INTEGER
        constraint Survey_pk
            primary key,
    Description TEXT
);
CREATE TABLE IF NOT EXISTS "Answer"
(
    AnswerText TEXT,
    SurveyID   INTEGER
        constraint Answer_Survey_SurveyID_fk
            references Survey,
    UserID     INTEGER,
    QuestionID INTEGER
        constraint Answer_Question_questionid_fk
            references Question,
    constraint Answer_pk
        primary key (UserID, QuestionID)
);
