列基数和总行数相等

Question

列基数和总行数相等

Uma*_*air 5 mysql performance optimization query-performance

我有一个包含 128'914'635 行的表。某些列的基数（即地址、姓氏、名字）等于表中的总行数 (128'914'635)。这个表上的查询真的很慢，当我在连接中使用这个表时，它们不使用任何索引。

你有什么想法为什么基数等于表中的总数或行数？

运行分析表
同表整理也没有在解释扩展中进行转换
力指数不起作用

我们在下面的问题中描述了一个类似的问题。唯一的区别是我们有相同的整理表，而 Explain Extended 没有显示显式转换。

MySQL忽略索引，索引基数与表中的记录数相同（？！）

但是为什么仍然没有使用索引并且字段（地址字段）的基数与表行数相同？

表定义

CREATE TABLE `Datasupplied_Consumer_Final` (
  `AddressID` varchar(100) DEFAULT NULL,
  `IndividualId` varchar(100) DEFAULT NULL,
  `personfirstname` char(30) DEFAULT NULL,
  `personmiddleinitial` char(1) DEFAULT NULL,
  `personlastname` char(30) DEFAULT NULL,
  `PersonSurnameSuffix` varchar(100) DEFAULT NULL,
  `persontitleofrespect` varchar(100) DEFAULT NULL,
  `housenumber` varchar(100) DEFAULT NULL,
  `predirection` varchar(100) DEFAULT NULL,
  `streetname` varchar(100) DEFAULT NULL,
  `streetsuffix` varchar(100) DEFAULT NULL,
  `postdirection` varchar(100) DEFAULT NULL,
  `unitdesignator` varchar(100) DEFAULT NULL,
  `unitdesignatornumber` varchar(100) DEFAULT NULL,
  `primaryaddress` char(47) DEFAULT NULL,
  `secondaryaddress` char(12) DEFAULT NULL,
  `state` varchar(2) DEFAULT NULL,
  `ZipCode` varchar(5) DEFAULT NULL,
  `Zip_4` varchar(4) DEFAULT NULL,
  `del_point_check_digit` varchar(100) DEFAULT NULL,
  `msa` varchar(100) DEFAULT NULL,
  `countycode` varchar(100) DEFAULT NULL,
  `countyname` varchar(100) DEFAULT NULL,
  `citynameabbr` varchar(100) DEFAULT NULL,
  `cityname` char(30) DEFAULT NULL,
  `carrier_route` varchar(100) DEFAULT NULL,
  `censustract` varchar(100) DEFAULT NULL,
  `censusblock` varchar(100) DEFAULT NULL,
  `latitude` varchar(100) DEFAULT NULL,
  `longitude` varchar(100) DEFAULT NULL,
  `timezone` varchar(100) DEFAULT NULL,
  `Xaxis` varchar(100) DEFAULT NULL,
  `Yaxis` varchar(100) DEFAULT NULL,
  `Zaxis` varchar(100) DEFAULT NULL,
  `dpv_code` varchar(100) DEFAULT NULL,
  `NumberOfSources` varchar(100) DEFAULT NULL,
  `dwellingtype` varchar(100) DEFAULT NULL,
  `secondaryaddresspresent` varchar(100) DEFAULT NULL,
  `livingunitid` varchar(100) DEFAULT NULL,
  `RDID` varchar(100) DEFAULT NULL,
  `areacode` varchar(100) DEFAULT NULL,
  `Phone` varchar(100) DEFAULT NULL,
  `estimatedincomecode` varchar(100) DEFAULT NULL,
  `homeownerprobabilitymodel` varchar(100) DEFAULT NULL,
  `lengthofresidence` varchar(100) DEFAULT NULL,
  `lengthofresidencecode` varchar(100) DEFAULT NULL,
  `numberofpersonsinlivingunit` varchar(100) DEFAULT NULL,
  `presenceofchildren` varchar(100) DEFAULT NULL,
  `NumberOfChildren` varchar(100) DEFAULT NULL,
  `ChildrenAge00_02` varchar(100) DEFAULT NULL,
  `ChildrenAge00_02Male` varchar(100) DEFAULT NULL,
  `ChildrenAge00_02Female` varchar(100) DEFAULT NULL,
  `ChildrenAge00_02Unknown` varchar(100) DEFAULT NULL,
  `ChildrenAge03_05` varchar(100) DEFAULT NULL,
  `ChildrenAge03_05Male` varchar(100) DEFAULT NULL,
  `ChildrenAge03_05Female` varchar(100) DEFAULT NULL,
  `ChildrenAge03_05Unknown` varchar(100) DEFAULT NULL,
  `ChildrenAge06_10` varchar(100) DEFAULT NULL,
  `ChildrenAge06_10Male` varchar(100) DEFAULT NULL,
  `ChildrenAge06_10Female` varchar(100) DEFAULT NULL,
  `ChildrenAge06_10Unknown` varchar(100) DEFAULT NULL,
  `ChildrenAge11_15` varchar(100) DEFAULT NULL,
  `ChildrenAge11_15Male` varchar(100) DEFAULT NULL,
  `ChildrenAge11_15Female` varchar(100) DEFAULT NULL,
  `ChildrenAge11_15Unknown` varchar(100) DEFAULT NULL,
  `ChildrenAge16_17` varchar(100) DEFAULT NULL,
  `ChildrenAge16_17Male` varchar(100) DEFAULT NULL,
  `ChildrenAge16_17Female` varchar(100) DEFAULT NULL,
  `ChildrenAge16_17Unknown` varchar(100) DEFAULT NULL,
  `persongender` char(1) DEFAULT NULL,
  `persondateofbirthyear` varchar(100) DEFAULT NULL,
  `persondateofbirthmonth` varchar(100) DEFAULT NULL,
  `persondateofbirthday` varchar(100) DEFAULT NULL,
  `personexactage` varchar(100) DEFAULT NULL,
  `personagecode` varchar(100) DEFAULT NULL,
  `Males_18_24` varchar(100) DEFAULT NULL,
  `Females_18_24` varchar(100) DEFAULT NULL,
  `Unknowngender_18_24` varchar(100) DEFAULT NULL,
  `Males_25_34` varchar(100) DEFAULT NULL,
  `Females_25_34` varchar(100) DEFAULT NULL,
  `Unknowngender_25_34` varchar(100) DEFAULT NULL,
  `Males_35_44` varchar(100) DEFAULT NULL,
  `Females_35_44` varchar(100) DEFAULT NULL,
  `Unknowngender_35_44` varchar(100) DEFAULT NULL,
  `Males_45_54` varchar(100) DEFAULT NULL,
  `Females_45_54` varchar(100) DEFAULT NULL,
  `Unknowngender_45_54` varchar(100) DEFAULT NULL,
  `Males_55_64` varchar(100) DEFAULT NULL,
  `Females_55_64` varchar(100) DEFAULT NULL,
  `Unknowngender_55_64` varchar(100) DEFAULT NULL,
  `Males_65_74` varchar(100) DEFAULT NULL,
  `Females_65_74` varchar(100) DEFAULT NULL,
  `Unknowngender_65_74` varchar(100) DEFAULT NULL,
  `Males_75_Plus` varchar(100) DEFAULT NULL,
  `Females_75_Plus` varchar(100) DEFAULT NULL,
  `Unknowngender_75_Plus` varchar(100) DEFAULT NULL,
  `personmaritalstatus` varchar(100) DEFAULT NULL,
  `InferredAge` varchar(100) DEFAULT NULL,
  `occupationgroup` varchar(100) DEFAULT NULL,
  `personoccupation` varchar(100) DEFAULT NULL,
  `ethniccode` varchar(100) DEFAULT NULL,
  `languagecode` varchar(100) DEFAULT NULL,
  `ethnicgroup` varchar(100) DEFAULT NULL,
  `religioncode` varchar(100) DEFAULT NULL,
  `hispaniccountrycode` varchar(100) DEFAULT NULL,
  `personeducation` varchar(100) DEFAULT NULL,
  `businessowner` varchar(100) DEFAULT NULL,
  `EthnicConfidenceCode` varchar(100) DEFAULT NULL,
  `InferredHouseholdRank` varchar(100) DEFAULT NULL,
  `NumberOfAdults` varchar(100) DEFAULT NULL,
  `GenerationsInHousehold` varchar(100) DEFAULT NULL,
  `PresenceOfCreditCard` varchar(100) DEFAULT NULL,
  `presenceofgoldorplatinumcreditcard` varchar(100) DEFAULT NULL,
  `PresenceOfPremiumCreditCard` varchar(100) DEFAULT NULL,
  `PresenceOfUpscaleRetailCard` varchar(100) DEFAULT NULL,
  `PresenceOfBankCard` varchar(100) DEFAULT NULL,
  `GasDeptRetailCardHolder` varchar(100) DEFAULT NULL,
  `americanexpresscard` varchar(100) DEFAULT NULL,
  `CreditRating` varchar(100) DEFAULT NULL,
  `investment` varchar(100) DEFAULT NULL,
  `investmentstocksecurities` varchar(100) DEFAULT NULL,
  `Networth` varchar(100) DEFAULT NULL,
  `NumberOfLinesOfCredit` varchar(100) DEFAULT NULL,
  `Credit_RangeOfNewCredit` varchar(100) DEFAULT NULL,
  `AmericanExpressGoldPremium` varchar(100) DEFAULT NULL,
  `DiscoverGoldPremium` varchar(100) DEFAULT NULL,
  `DiscoverRegular` varchar(100) DEFAULT NULL,
  `GasolineOrRetailCardGoldPremium` varchar(100) DEFAULT NULL,
  `GASOLINE OR RETAIL CARD REGULAR` varchar(100) DEFAULT NULL,
  `MastercardGoldPremium` varchar(100) DEFAULT NULL,
  `MastercardRegular` varchar(100) DEFAULT NULL,
  `VisaGoldPremium` varchar(100) DEFAULT NULL,
  `VisaRegular` varchar(100) DEFAULT NULL,
  `CREDIT CARD INDICATOR` varchar(100) DEFAULT NULL,
  `BANK CARD HOLDER` varchar(100) DEFAULT NULL,
  `GAS/DEPARTMENT/RETAIL CARD HOLDER` varchar(100) DEFAULT NULL,
  `TravelAndEntertainmentCardHolder` varchar(100) DEFAULT NULL,
  `CreditCardholderUnknownType` varchar(100) DEFAULT NULL,
  `PREMIUM CARD HOLDER` varchar(100) DEFAULT NULL,
  `UPSCALE (DEPARTMENT STORE) CARD HOLDER` varchar(100) DEFAULT NULL,
  `CreditCardUser` varchar(100) DEFAULT NULL,
  `CreditCardNewIssue` varchar(100) DEFAULT NULL,
  `BANK CARD - PRESENCE IN HOUSEHOLD` varchar(100) DEFAULT NULL,
  `Investing_Active` varchar(100) DEFAULT NULL,
  `InvestmentsPersonal` varchar(100) DEFAULT NULL,
  `InvestmentsRealEstate` varchar(100) DEFAULT NULL,
  `InvestingFinanceGrouping` varchar(100) DEFAULT NULL,
  `InvestmentsForeign` varchar(100) DEFAULT NULL,
  `InvestmentEstimatedResidentialPropertiesOwned` varchar(100) DEFAULT NULL,
  `AssimilationCodes` varchar(100) DEFAULT NULL,
  `valuehunter` varchar(100) DEFAULT NULL,
  `opportunityseekers` varchar(100) DEFAULT NULL,
  `newsandfinancial` varchar(100) DEFAULT NULL,
  `automotivebuff` varchar(100) DEFAULT NULL,
  `bookreader` varchar(100) DEFAULT NULL,
  `MembershipClub` varchar(100) DEFAULT NULL,
  `computerowner` varchar(100) DEFAULT NULL,
  `cookingenthusiast` varchar(100) DEFAULT NULL,
  `do_it_yourselfers` varchar(100) DEFAULT NULL,
  `exerciseenthusiast` varchar(100) DEFAULT NULL,
  `Gardener` varchar(100) DEFAULT NULL,
  `golfenthusiasts` varchar(100) DEFAULT NULL,
  `homedecoratingenthusiast` varchar(100) DEFAULT NULL,
  `outdoorenthusiast` varchar(100) DEFAULT NULL,
  `outdoorsportslover` varchar(100) DEFAULT NULL,
  `photography` varchar(100) DEFAULT NULL,
  `traveler` varchar(100) DEFAULT NULL,
  `pets` varchar(100) DEFAULT NULL,
  `cats` varchar(100) DEFAULT NULL,
  `dogs` varchar(100) DEFAULT NULL,
  `mailresponder` varchar(100) DEFAULT NULL,
  `RespondedtoCatalog` varchar(100) DEFAULT NULL,
  `sweepstakes` varchar(100) DEFAULT NULL,
  `religiousmagazine` varchar(100) DEFAULT NULL,
  `malemerchbuyer` varchar(100) DEFAULT NULL,
  `femalemerchbuyer` varchar(100) DEFAULT NULL,
  `crafts_hobbmerchbuyer` varchar(100) DEFAULT NULL,
  `gardening_farmingbuyer` varchar(100) DEFAULT NULL,
  `bookbuyer` varchar(100) DEFAULT NULL,
  `collect_specialfoodsbuyer` varchar(100) DEFAULT NULL,
  `religiouscontributor` varchar(100) DEFAULT NULL,
  `politicalcontributor` varchar(100) DEFAULT NULL,
  `health_institutioncontributor` varchar(100) DEFAULT NULL,
  `charitable` varchar(100) DEFAULT NULL,
  `generalcontributor` varchar(100) DEFAULT NULL,
  `donatestoenvironmentalcauses` varchar(100) DEFAULT NULL,
  `donatesbymail` varchar(100) DEFAULT NULL,
  `veteraninhousehold` varchar(100) DEFAULT NULL,
  `HeavyBusinessTravelers` varchar(100) DEFAULT NULL,
  `hightechleader` varchar(100) DEFAULT NULL,
  `Smoker` varchar(100) DEFAULT NULL,
  `MailOrderBuyer` varchar(100) DEFAULT NULL,
  `OnlinePurchasingIndicator` varchar(100) DEFAULT NULL,
  `ApparelWomens` varchar(100) DEFAULT NULL,
  `ApparelWomensPetite` varchar(100) DEFAULT NULL,
  `ApparelWomensPlusSizes` varchar(100) DEFAULT NULL,
  `YoungWomensApparel` varchar(100) DEFAULT NULL,
  `ApparelMens` varchar(100) DEFAULT NULL,
  `ApparelMensBigAndTall` varchar(100) DEFAULT NULL,
  `YoungMensApparel` varchar(100) DEFAULT NULL,
  `ApparelChildrens` varchar(100) DEFAULT NULL,
  `HealthAndBeauty` varchar(100) DEFAULT NULL,
  `BeautyCosmetics` varchar(100) DEFAULT NULL,
  `Jewelry` varchar(100) DEFAULT NULL,
  `Luggage` varchar(100) DEFAULT NULL,
  `COMMUNITY INVOLVEMENT - CAUSES SUPPORTED FINANCIALLY` varchar(100) DEFAULT NULL,
  `AnimalWelfareCharitableDonation` varchar(100) DEFAULT NULL,
  `ArtsOrCulturalCharitableDonation` varchar(100) DEFAULT NULL,
  `ChildrensCharitableDonation` varchar(100) DEFAULT NULL,
  `ENVIRONMENT OR WILDLIFE  CHARITABLE DONATION` varchar(100) DEFAULT NULL,
  `EnvironmentalIssuesCharitableDonation` varchar(100) DEFAULT NULL,
  `InternationalAidCharitableDonation` varchar(100) DEFAULT NULL,
  `PoliticalCharitableDonation` varchar(100) DEFAULT NULL,
  `PoliticalConservativeCharitableDonation` varchar(100) DEFAULT NULL,
  `PoliticalLiberalCharitableDonation` varchar(100) DEFAULT NULL,
  `VeteransCharitableDonation` varchar(100) DEFAULT NULL,
  `CharitableDonations_Other` varchar(100) DEFAULT NULL,
  `CommunityCharities` varchar(100) DEFAULT NULL,
  `Parenting` varchar(100) DEFAULT NULL,
  `SingleParent` varchar(100) DEFAULT NULL,
  `ChildrensApparelInfantsAndToddlers` varchar(100) DEFAULT NULL,
  `ChildrensLearningAndActivityToys` varchar(100) DEFAULT NULL,
  `ChildrensProductsGeneralBabyCare` varchar(100) DEFAULT NULL,
  `ChildrensProductsGeneralBackToSchool` varchar(100) DEFAULT NULL,
  `ChildrensProductsGeneral` varchar(100) DEFAULT NULL,
  `YoungAdultInHousehold` varchar(100) DEFAULT NULL,
  `SeniorAdultInHousehold` varchar(100) DEFAULT NULL,
  `ChildrensInterests` varchar(100) DEFAULT NULL,
  `Grandchildren` varchar(100) DEFAULT NULL,
  `ChristianFamilies` varchar(100) DEFAULT NULL,
  `Equestrian` varchar(100) DEFAULT NULL,
  `Name` varchar(100) DEFAULT NULL,
  `ID` int(11) NOT NULL AUTO_INCREMENT,
  `consumer_email` varchar(100) DEFAULT NULL,
  PRIMARY KEY (`ID`),
  KEY `ind_personlastname` (`personlastname`),
  KEY `ind_personfirstname` (`personfirstname`),
  KEY `ind_primaryaddress` (`primaryaddress`),
  KEY `ind_state` (`state`),
  KEY `ind_zipcode` (`ZipCode`),
  KEY `ind_city` (`cityname`),
  KEY `ind_estimatedincomecode` (`estimatedincomecode`),
  KEY `ind_personmaritalstatus` (`personmaritalstatus`),
  KEY `ind_persongender` (`persongender`)
) ENGINE=InnoDB AUTO_INCREMENT=43456212 DEFAULT CHARSET=latin1 <br>

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和...

CREATE TABLE `master_consumer_export_06172013_FullMatchBack_Final` (
  `reg_source` varchar(100) DEFAULT NULL,
  `reg_addDate` varchar(100) DEFAULT NULL,
  `reg_firstName` varchar(100) DEFAULT NULL,
  `reg_lastName` varchar(100) DEFAULT NULL,
  `reg_add1` varchar(100) DEFAULT NULL,
  `reg_city` varchar(100) DEFAULT NULL,
  `reg_state` varchar(100) DEFAULT NULL,
  `reg_zip` varchar(100) DEFAULT NULL,
  `reg_phone` varchar(100) DEFAULT NULL,
  `reg_email` varchar(100) DEFAULT NULL,
  `reg_optinUrlClean` varchar(100) DEFAULT NULL,
  `reg_IPClean` varchar(100) DEFAULT NULL,
  `reg_dateTime` varchar(100) DEFAULT NULL,
  `reg_dateStandard` varchar(100) DEFAULT NULL,
  `duplicate` varchar(100) DEFAULT NULL,
  `DeliveryLine1` varchar(100) DEFAULT NULL,
  `DeliveryLine2` varchar(100) DEFAULT NULL,
  `city` varchar(100) DEFAULT NULL,
  `state` varchar(100) DEFAULT NULL,
  `ZIPCode` varchar(100) DEFAULT NULL,
  `FullZIPCode` varchar(100) DEFAULT NULL,
  `Latitude` varchar(100) DEFAULT NULL,
  `Longitude` varchar(100) DEFAULT NULL,
  `Precision` varchar(100) DEFAULT NULL,
  `DeliveryPointBarcode` varchar(100) DEFAULT NULL,
  `CarrierRoute` varchar(100) DEFAULT NULL,
  `CountyFIPS` varchar(100) DEFAULT NULL,
  `CountyName` varchar(100) DEFAULT NULL,
  `CongressionalDistrict` varchar(100) DEFAULT NULL,
  `Deliverable` varchar(100) DEFAULT NULL,
  `RecordType` varchar(100) DEFAULT NULL,
  `RDI` varchar(100) DEFAULT NULL,
  `CMRA` varchar(100) DEFAULT NULL,
  `processingDate` varchar(100) DEFAULT NULL,
  `suppressed_by_master_suppression` varchar(100) DEFAULT NULL,
  `master_consumer_id` varchar(100) DEFAULT NULL,
  `quickiesuppressioncode` varchar(100) DEFAULT NULL,
  `EmailUploadedOnQuickie` varchar(100) DEFAULT NULL,
  `MC` varchar(100) DEFAULT NULL,
  `col` varchar(100) DEFAULT NULL,
  `IsBadEMail` varchar(100) DEFAULT NULL,
  `Domain_From_Email` varchar(100) DEFAULT NULL,
  `Fgx_rdi` varchar(100) DEFAULT NULL,
  `Fgx_Email` varchar(100) DEFAULT NULL,
  KEY `ind_9090909` (`reg_email`),
  KEY `ind_90909address` (`reg_add1`),
  KEY `ind_999900_0090_I` (`DeliveryLine1`),
  KEY `ind_9090909999` (`state`),
  KEY `ind_9090909999Ti` (`city`),
  KEY `ind_9987comb` (`DeliveryLine1`,`reg_lastName`) 
) ENGINE=InnoDB DEFAULT CHARSET=latin1

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现在下面是解释扩展

EXPLAIN EXTENDED 
UPDATE Datasupplied_Consumer_Final a,master_consumer_export_06172013_FullMatchBack_Final b
SET a.consumer_email = b.reg_email
WHERE a.primaryaddress=b.DeliveryLine1
AND a.personlastname=b.reg_lastname
AND LEFT(a.personfirstname,1) = LEFT(b.reg_firstname,1)
AND a.cityname=b.city
AND a.state =b.state
AND IFNULL(b.DeliveryLine1,'')<>''
AND IFNULL(a.primaryaddress,'')<>''
AND IFNULL(b.reg_email,'')<>''
AND IFNULL(a.personfirstname,'')<>''
AND IFNULL(b.reg_firstname,'')<>''
AND IFNULL(a.personlastname,'')<>''
AND IFNULL(b.reg_lastname,'')<>''
AND IFNULL(a.cityname,'')<>''
AND IFNULL(b.city,'')<>''
AND IFNULL(a.state,'')<>''
AND IFNULL(b.state,'')<>''  

+----+-------------+-------+------+----------------------------------------------------------------+-------------------+---------+----------------------------+----------+----------+-------------+
| id | select_type | table | type | possible_keys                                                  | key               | key_len | ref                        | rows     | filtered | Extra       |
+----+-------------+-------+------+----------------------------------------------------------------+-------------------+---------+----------------------------+----------+----------+-------------+
|  1 | SIMPLE      | a     | ALL  | ind_personlastname,ind_primaryaddress,ind_state,ind_city       | NULL              | NULL    | NULL                       | 37751230 |   100.00 | Using where |
|  1 | SIMPLE      | b     | ref  | ind_999900_0090_I,ind_9090909999,ind_9090909999Ti,ind_9987comb | ind_999900_0090_I | 103     | load_file.a.primaryaddress |        1 |   100.00 | Using where |
+----+-------------+-------+------+----------------------------------------------------------------+-------------------+---------+----------------------------+----------+----------+-------------+

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显示两个表的索引

mysql> SHOW INDEXES FROM Datasupplied_Consumer_Final;
+-----------------------------+------------+-------------------------+--------------+---------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Table                       | Non_unique | Key_name                | Seq_in_index | Column_name         | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment | Index_comment |
+-----------------------------+------------+-------------------------+--------------+---------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+
| Datasupplied_Consumer_Final |          0 | PRIMARY                 |            1 | ID                  | A         |    37751230 |     NULL | NULL   |      | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_personlastname      |            1 | personlastname      | A         |     1451970 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_personfirstname     |            1 | personfirstname     | A         |     1797677 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_primaryaddress      |            1 | primaryaddress      | A         |    37751230 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_state               |            1 | state               | A         |       42899 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_zipcode             |            1 | ZipCode             | A         |      129729 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_city                |            1 | cityname            | A         |      243556 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_estimatedincomecode |            1 | estimatedincomecode | A         |       28005 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_personmaritalstatus |            1 | personmaritalstatus | A         |           2 |     NULL | NULL   | YES  | BTREE      |         |               |
| Datasupplied_Consumer_Final |          1 | ind_persongender        |            1 | persongender        | A         |           2 |     NULL | NULL   | YES  | BTREE      |         |               |
+-----------------------------+------------+-------------------------+--------------+---------------------+-----------+-------------+----------+--------+------+------------+---------+---------------+  

mysql> SHOW INDEXES FROM master_consumer_export_06172013_FullMatchBack_Final;
+-----------------------------------------------------+------------+-------------------+--------------+---------------+-----------+-------------+----------+--------+------+------------+--

Answer 1

Ric*_*mes 0

DROP INDEX ind_999900_0090_I;，因为它似乎妨碍了使用更好的（复合）索引。

当您执行此操作时，将primaryaddress 上的索引替换为，INDEX(primaryaddress, personlastname)看看它是否将从另一个表开始。

由于这些是巨大的表，并且子句中基本上没有任何内容WHERE可以阻止表扫描，因此您可能希望将查询拆分为块。请参阅我关于分块的讨论。

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