-- Database schema
| Country : CountryCode [ TEXT ] primary_key , ShortName [ TEXT ] , TableName [ TEXT ] , LongName [ TEXT ] , Alpha2Code [ TEXT ] , CurrencyUnit [ TEXT ] , SpecialNotes [ TEXT ] , Region [ TEXT ] , IncomeGroup [ TEXT ] , Wb2Code [ TEXT ] , NationalAccountsBaseYear [ TEXT ] , NationalAccountsReferenceYear [ TEXT ] , SnaPriceValuation [ TEXT ] , LendingCategory [ TEXT ] , OtherGroups [ TEXT ] , SystemOfNationalAccounts [ TEXT ] , AlternativeConversionFactor [ TEXT ] , PppSurveyYear [ TEXT ] , BalanceOfPaymentsManualInUse [ TEXT ] , ExternalDebtReportingStatus [ TEXT ] , SystemOfTrade [ TEXT ] , GovernmentAccountingConcept [ TEXT ] , ImfDataDisseminationStandard [ TEXT ] , LatestPopulationCensus [ TEXT ] , LatestHouseholdSurvey [ TEXT ] , SourceOfMostRecentIncomeAndExpenditureData [ TEXT ] , VitalRegistrationComplete [ TEXT ] , LatestAgriculturalCensus [ TEXT ] , LatestIndustrialData [ INTEGER ] , LatestTradeData [ INTEGER ] , LatestWaterWithdrawalData [ INTEGER ] | Series : SeriesCode [ TEXT ] primary_key , Topic [ TEXT ] , IndicatorName [ TEXT ] , ShortDefinition [ TEXT ] , LongDefinition [ TEXT ] , UnitOfMeasure [ TEXT ] , Periodicity [ TEXT ] , BasePeriod [ TEXT ] , OtherNotes [ INTEGER ] , AggregationMethod [ TEXT ] , LimitationsAndExceptions [ TEXT ] , NotesFromOriginalSource [ TEXT ] , GeneralComments [ TEXT ] , Source [ TEXT ] , StatisticalConceptAndMethodology [ TEXT ] , DevelopmentRelevance [ TEXT ] , RelatedSourceLinks [ TEXT ] , OtherWebLinks [ INTEGER ] , RelatedIndicators [ INTEGER ] , LicenseType [ TEXT ] | CountryNotes : Countrycode [ TEXT ] CountryNotes.Countrycode = Country.CountryCode , Seriescode [ TEXT ] CountryNotes.Seriescode = Series.SeriesCode , Description [ TEXT ] | Footnotes : Countrycode [ TEXT ] Footnotes.Countrycode = Country.CountryCode , Seriescode [ TEXT ] Footnotes.Seriescode = Series.SeriesCode , Year [ TEXT ] , Description [ TEXT ] | Indicators : CountryName [ TEXT ] , CountryCode [ TEXT ] Indicators.CountryCode = Country.CountryCode , IndicatorName [ TEXT ] , IndicatorCode [ TEXT ] , Year [ INTEGER ] , Value [ INTEGER ] | SeriesNotes : Seriescode [ TEXT ] SeriesNotes.Seriescode = Series.SeriesCode , Year [ TEXT ] , Description [ TEXT ] |
-- -- How many countries are having their country's footnotes described as "unspecified"? Please provide the full names of any three of those countries.

SELECT COUNT(DISTINCT T1.CountryCode)  FROM Country AS T1 INNER JOIN Footnotes AS T2 ON T1.CountryCode = T2.Countrycode WHERE T2.Description = 'Unspecified' OR T2.Description = 'Not specified' UNION SELECT T1.LongName FROM Country AS T1 INNER JOIN Footnotes AS T2 ON T1.CountryCode = T2.Countrycode WHERE T2.Description = 'Unspecified' OR T2.Description = 'Not specified' LIMIT 4;