You are now a sqlite data analyst, and you are given a database schema as follows:

    【Schema】
    【DB_ID】 legislator
【Schema】
# Table: current-terms
[
(address:TEXT),
(bioguide:TEXT, Primary Key, Examples: [A000055, A000360, A000367]),
(caucus:TEXT, Examples: [Democrat]),
(chamber:TEXT, Examples: [senate, house]),
(class:REAL, Examples: [1.0, 2.0, 3.0]),
(contact_form:TEXT),
(district:REAL, Examples: [13.0, 1.0, 3.0]),
(end:TEXT, Primary Key, Examples: [1999-01-03, 2001-01-03, 2003-01-03]),
(fax:TEXT, Examples: [202-228-6321, 202-228-0514, 202-224-1651]),
(last:TEXT, Examples: [Menendez]),
(name:TEXT, Examples: [Stewart Lee Udall, Morris K. Udall, Mark Udall]),
(office:TEXT, Examples: [713 Hart Senate Office Building]),
(party:TEXT, Examples: [Democrat, Republican, Independent]),
(party_affiliations:TEXT),
(phone:TEXT, Examples: [202-224-2315, 202-224-3441, 202-224-4524]),
(relation:TEXT, Examples: [son, nephew, cousin]),
(rss_url:TEXT),
(start:TEXT, Examples: [1993-01-05, 1995-01-04, 1997-01-07]),
(state:TEXT, Examples: [OH, WA, MD]),
(state_rank:TEXT, Examples: [senior, junior]),
(title:TEXT, Examples: [Minority Whip, Majority Whip, Minority Leader]),
(type:TEXT, Examples: [rep, sen]),
(url:TEXT)
]
# Table: historical
[
(ballotpedia_id:TEXT, Examples: [Mo Cowan, Jo Bonner, Rodney Alexander]),
(bioguide_id:TEXT, Primary Key, Examples: [A000001, A000002, A000003]),
(bioguide_previous_id:TEXT, Examples: [['F000246'], ['L000266'], ['W000790']]),
(birthday_bio:TEXT, Examples: [1745-04-02, 1742-03-21, 1743-06-16]),
(cspan_id:TEXT, Examples: [12590.0, 4479.0, 103.0]),
(fec_id:TEXT, Examples: [['S6CO00168'], ['S2MN00126'], ['S0ID00057']]),
(first_name:TEXT, Examples: [Richard, Theodorick, Aedanus]),
(gender_bio:TEXT, Examples: [M, F]),
(google_entity_id_id:TEXT, Examples: [kg:/m/02pz46, kg:/m/033mf4, kg:/m/03yccv]),
(govtrack_id:INTEGER, Examples: [401222, 401521, 402032]),
(house_history_alternate_id:TEXT, Examples: [13283.0]),
(house_history_id:REAL, Examples: [9479.0, 10177.0, 10687.0]),
(icpsr_id:REAL, Examples: [507.0, 786.0, 1260.0]),
(last_name:TEXT, Examples: [Bassett, Bland, Burke]),
(lis_id:TEXT, Examples: [S134, S135, S138]),
(maplight_id:TEXT, Examples: [232.0, 581.0, 585.0]),
(middle_name:TEXT, Examples: [Samuel, Henry, Jenifer]),
(nickname_name:TEXT, Examples: [of Carrollton, of Colchester, of Milton]),
(official_full_name:TEXT, Examples: [Enid Greene Waldholtz]),
(opensecrets_id:TEXT, Examples: [N00008333, N00006953, N00009160]),
(religion_bio:TEXT, Examples: [Baptist, Roman Catholic, Methodist]),
(suffix_name:TEXT, Examples: [Jr., Sr., II]),
(thomas_id:TEXT, Examples: [01308, 01270, 01281]),
(votesmart_id:TEXT, Examples: [52156.0, 128775.0, 26829.0]),
(wikidata_id:TEXT, Examples: [Q518823, Q1749152, Q380504]),
(wikipedia_id:TEXT, Examples: [Richard Bassett (politician)])
]
# Table: current
[
(ballotpedia_id:TEXT, Examples: [Sherrod Brown, Maria Cantwell, Ben Cardin]),
(bioguide_id:TEXT, Primary Key, Examples: [A000055, A000360, A000367]),
(birthday_bio:DATE, Examples: [1952-11-09]),
(cspan_id:REAL, Primary Key, Examples: [45516.0, 5.0, 1033767.0]),
(fec_id:TEXT, Examples: [['H2OH13033', 'S6OH00163']]),
(first_name:TEXT, Examples: [Sherrod, Maria, Benjamin]),
(gender_bio:TEXT, Examples: [M, F]),
(google_entity_id_id:TEXT, Examples: [kg:/m/034s80, kg:/m/01x68t, kg:/m/025k3k]),
(govtrack_id:INTEGER, Examples: [400050, 300018, 400064]),
(house_history_id:REAL, Examples: [9996.0, 10608.0, 10629.0]),
(icpsr_id:REAL, Examples: [29389.0, 39310.0, 15408.0]),
(last_name:TEXT, Examples: [Brown, Cantwell, Cardin]),
(lis_id:TEXT, Examples: [S307, S275, S308]),
(maplight_id:REAL, Examples: [168.0, 544.0, 182.0]),
(middle_name:TEXT, Examples: [L., Richard, P.]),
(nickname_name:TEXT, Examples: [Bob, Bernie, Jim]),
(official_full_name:TEXT, Examples: [Sherrod Brown, Maria Cantwell, Benjamin L. Cardin]),
(opensecrets_id:TEXT, Examples: [N00003535, N00007836, N00001955]),
(religion_bio:TEXT, Examples: [Lutheran, Roman Catholic, Jewish]),
(suffix_name:TEXT, Examples: [Jr., III, II]),
(thomas_id:INTEGER, Examples: [136, 172, 174]),
(votesmart_id:REAL, Examples: [27018.0, 27122.0, 26888.0]),
(wikidata_id:TEXT, Examples: [Q381880, Q22250, Q723295]),
(wikipedia_id:TEXT, Examples: [Sherrod Brown, Maria Cantwell, Ben Cardin])
]
# Table: social-media
[
(bioguide:TEXT, Primary Key, Examples: [A000055, A000360, A000367]),
(facebook:TEXT, Examples: [congresswomanaumuaamata]),
(facebook_id:REAL, Examples: [1537155909907320.0, 186203844738421.0, 351671691660938.0]),
(govtrack:REAL, Examples: [412664.0, 412428.0, 412667.0]),
(instagram:TEXT, Examples: [senjoniernst, senatorwarner, SenWhitehouse]),
(instagram_id:REAL, Examples: [1582702853.0, 515327940.0, 1559860900.0]),
(thomas:INTEGER, Examples: [2222, 2019, 2283]),
(twitter:TEXT, Examples: [RepAmata, RepToddYoung, SenJoniErnst]),
(twitter_id:REAL, Examples: [3026622545.0, 234128524.0, 2856787757.0]),
(youtube:TEXT, Examples: [RepToddYoung, RepYoder, RepJohnYarmuth]),
(youtube_id:TEXT, Examples: [UCGdrLQbt1PYDTPsampx4t1A])
]
# Table: historical-terms
[
(address:TEXT),
(bioguide:TEXT, Primary Key, Examples: [A000001, A000002, A000003]),
(chamber:TEXT, Examples: [house, senate]),
(class:REAL, Examples: [2.0, 1.0, 3.0]),
(contact_form:TEXT),
(district:REAL, Examples: [9.0, 2.0, 6.0]),
(end:TEXT, Examples: [1793-03-03, 1791-03-03, 1795-03-03]),
(fax:TEXT, Examples: [202-228-6363, 202-226-6299, 202-226-0893]),
(last:TEXT, Examples: [Levy, Lambert, Bono]),
(middle:TEXT),
(name:TEXT),
(office:TEXT, Examples: [248 Russell Senate Office Building]),
(party:TEXT, Examples: [Anti-Administration, Pro-Administration, Republican]),
(party_affiliations:TEXT),
(phone:TEXT, Examples: [202-224-4024, 202-224-4543, 202-225-2706]),
(relation:TEXT),
(rss_url:TEXT),
(start:TEXT, Examples: [1789-03-04, 1790-01-01, 1791-10-24]),
(state:TEXT, Examples: [DE, VA, SC]),
(state_rank:TEXT, Examples: [junior, senior]),
(title:TEXT, Examples: [Majority Leader, Speaker]),
(type:TEXT, Examples: [sen, rep]),
(url:TEXT)
]
【Foreign keys】
current-terms.bioguide=current.bioguide_id
social-media.bioguide=current.bioguide_id
historical-terms.bioguide=historical.bioguide_id

    【Question】
    How many official social media does Mark Warner have? official social media refers to facebook is not null, instagram is not null, twitter is not null, youtube is not null; Mark Warner is an official_full_name; official_full_name refers to first_name, last_name

    【Evidence】
    official social media refers to facebook is not null, instagram is not null, twitter is not null, youtube is not null; Mark Warner is an official_full_name; official_full_name refers to first_name, last_name

    Please read and understand the database schema carefully, and generate an executable SQL based on the user's question and evidence. 

SQL: SELECT CASE WHEN T1.facebook IS NOT NULL THEN 1 END + CASE WHEN T1.instagram IS NOT NULL THEN 1 END + CASE WHEN T1.twitter IS NOT NULL THEN 1 END + CASE WHEN T1.youtube IS NOT NULL THEN 1 END AS COUNTSOCIAL FROM `social-media` AS T1 INNER JOIN current AS T2 ON T1.bioguide = T2.bioguide_id WHERE T2.first_name = 'Mark' AND T2.last_name = 'Warner'