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単純なSELECT問合せ

例のとおりに操作する場合は、スクリプトbaggageschema_loaddata.sqlをダウンロードして、次に示すように実行します。このスクリプトにより、例で使用する表が作成され、表にデータがロードされます。

KVSTOREまたはKVLiteを起動し、SQL.shellを開きます。
java -jar lib/kvstore.jar kvlite -secure-config disable
java -jar lib/sql.jar -helper-hosts localhost:5000 -store kvstore
loadコマンドを使用して、スクリプトを実行します。
load -file baggageschema_loaddata.sql

列データのフェッチ

表から列を選択できます。そのためには、文のSELECTの後に目的の表の列名をリストします。FROM句の後に表の名前を指定します。子表からデータを取り出すには、parent.childのようなドット表記法を使用します。表の列をすべて選択するには、アスタリスク(*)ワイルドカード文字を使用します。SELECT文には、既存の列の値に基づく計算式を含めることもできます。

例1: 表BaggageInfoからすべてのデータを選択します。
SELECT * FROM BaggageInfo

説明: BaggageInfoスキーマには、いくつかの固定静的フィールドとJSON列が含まれます。静的フィールドは、チケット番号、フルネーム、性別、連絡先電話番号および確認番号です。手荷物情報はJSONとして格納され、ドキュメントの配列が移入されます。

出力(簡潔にするために結果の行のみを表示):
{"ticketNo":1762330498104,"fullName":"Michelle Payne","gender":"F","contactPhone":"575-781-6240","confNo":"RL3J4Q",
"bagInfo":[{
   "bagArrivalDate":"2019-02-02T23:59:00Z",   
   "flightLegs":[
      {"actions":[
           {"actionAt":"SFO","actionCode":"ONLOAD to IST","actionTime":"2019-02-02T12:10:00Z"},          
           {"actionAt":"SFO","actionCode":"BagTag Scan at SFO","actionTime":"2019-02-02T11:47:00Z"},
           {"actionAt":"SFO","actionCode":"Checkin at SFO","actionTime":"2019-02-02T10:01:00Z"}],
           "estimatedArrival":"2019-02-03T01:00:00Z", 
           "flightDate":"2019-02-02T12:00:00Z",
           "flightNo":"BM318",
           "fltRouteDest":"IST",
           "fltRouteSrc":"SFO"}, 
      {"actions":[
           {"actionAt":"IST","actionCode":"ONLOAD to ATH","actionTime":"2019-02-03T13:06:00Z"},
           {"actionAt":"IST","actionCode":"BagTag Scan at IST","actionTime":"2019-02-03T12:48:00Z"},
           {"actionAt":"IST","actionCode":"OFFLOAD from IST","actionTime":"2019-02-03T13:00:00Z"}],
           "estimatedArrival":"2019-02-03T12:12:00Z",
           "flightDate":"2019-02-02T13:10:00Z",
           "flightNo":"BM696",
           "fltRouteDest":"ATH",
           "fltRouteSrc":"IST"},
      {"actions":[
           {"actionAt":"JTR","actionCode":"Offload to Carousel at JTR","actionTime":"2019-02-03T00:06:00Z"}, 
           {"actionAt":"ATH","actionCode":"ONLOAD to JTR","actionTime":"2019-02-03T00:13:00Z"},
           {"actionAt":"ATH","actionCode":"OFFLOAD from ATH","actionTime":"2019-02-03T00:10:00Z"}],
           "estimatedArrival":"2019-02-03T00:12:00Z",
           "flightDate":"2019-2-2T12:10:00Z",
           "flightNo":"BM665",
           "fltRouteDest":"JTR",
           "fltRouteSrc":"ATH"}],  
     "id":"79039899186259",
     "lastActionCode":"OFFLOAD",
     "lastActionDesc":"OFFLOAD",
     "lastSeenStation":"JTR",
     "lastSeenTimeGmt":"2019-02-02T23:59:00Z",
     "routing":"SFO/IST/ATH/JTR",
     "tagNum":"17657806247861"}
]}
例2: BaggageInfo表から特定の列を選択するには、列名をカンマ区切りのリストとしてSELECT文に含めます。
SELECT fullName, contactPhone, gender FROM BaggageInfo

説明: 3つの静的フィールド(フルネーム、電話番号、性別)の値を表示する必要があります。

出力:
{"fullName":"Lucinda Beckman","contactPhone":"364-610-4444","gender":"M"}
{"fullName":"Adelaide Willard","contactPhone":"421-272-8082","gender":"M"}
{"fullName":"Raymond Griffin","contactPhone":"567-710-9972","gender":"F"}
{"fullName":"Elane Lemons","contactPhone":"600-918-8404","gender":"F"}
{"fullName":"Zina Christenson","contactPhone":"987-210-3029","gender":"M"}
{"fullName":"Zulema Martindale","contactPhone":"666-302-0028","gender":"F"}
{"fullName":"Dierdre Amador","contactPhone":"165-742-5715","gender":"M"}
{"fullName":"Henry Jenkins","contactPhone":"960-428-3843","gender":"F"}
{"fullName":"Rosalia Triplett","contactPhone":"368-769-5636","gender":"F"}
{"fullName":"Lorenzo Phil","contactPhone":"364-610-4444","gender":"M"}
{"fullName":"Gerard Greene","contactPhone":"395-837-3772","gender":"M"}
{"fullName":"Adam Phillips","contactPhone":"893-324-1064","gender":"M"}
{"fullName":"Doris Martin","contactPhone":"289-564-3497","gender":"F"}
{"fullName":"Joanne Diaz","contactPhone":"334-679-5105","gender":"F"}
{"fullName":"Omar Harvey","contactPhone":"978-191-8550","gender":"F"}
{"fullName":"Fallon Clements","contactPhone":"849-731-1334","gender":"M"}
{"fullName":"Lisbeth Wampler","contactPhone":"796-709-9501","gender":"M"}
{"fullName":"Teena Colley","contactPhone":"539-097-5220","gender":"M"}
{"fullName":"Michelle Payne","contactPhone":"575-781-6240","gender":"F"}
{"fullName":"Mary Watson","contactPhone":"131-183-0560","gender":"F"}
{"fullName":"Kendal Biddle","contactPhone":"619-956-8760","gender":"F"}

問合せの列名の置換

SELECT文を実行するときに、列に異なる名前を使用できます。問合せ内で名前を置き換えても列名は変更されませんが、返されるデータ内では置換された名前が使用されます。

例: 次の問合せは、結果のCONTACTATとして電話番号を返します。
SELECT contactPhone AS CONTACTAT FROM BaggageInfo

説明: 乗客の連絡先電話番号をフェッチして、CONTACTATとして表示する必要があります。

出力:
{"CONTACTAT":"960-428-3843"}
{"CONTACTAT":"368-769-5636"}
{"CONTACTAT":"364-610-4444"}
{"CONTACTAT":"395-837-3772"}
{"CONTACTAT":"893-324-1064"}
{"CONTACTAT":"289-564-3497"}
{"CONTACTAT":"334-679-5105"}
{"CONTACTAT":"978-191-8550"}
{"CONTACTAT":"849-731-1334"}
{"CONTACTAT":"796-709-9501"}
{"CONTACTAT":"539-097-5220"}
{"CONTACTAT":"575-781-6240"}
{"CONTACTAT":"131-183-0560"}
{"CONTACTAT":"619-956-8760"}
{"CONTACTAT":"364-610-4444"}
{"CONTACTAT":"421-272-8082"}
{"CONTACTAT":"567-710-9972"}
{"CONTACTAT":"600-918-8404"}
{"CONTACTAT":"987-210-3029"}
{"CONTACTAT":"666-302-0028"}
{"CONTACTAT":"165-742-5715"}

次に示すように、連結演算子||を使用して列を結合できます。

例: すべての顧客について、手荷物が最後に確認された場所と、手荷物が確認された時刻をフェッチします。

アプローチ1: 連結演算子を使用して、SELECTコマンドの出力として列名と静的テキストをフェッチします。
SELECT "The bag was last seen at " || 
bag.bagInfo[].lastSeenStation || " on " ||
bag.bagInfo[].bagArrivalDate AS Bag_Details FROM BaggageInfo bag
出力: 
{"Bag_Details":"The bag was last seen at BZN on 2019-03-15T10:13:00Z"}
{"Bag_Details":"The bag was last seen at MEL on 2019-02-04T10:08:00Z"}
{"Bag_Details":"The bag was last seen at MEL on 2019-02-25T20:15:00Z"}
{"Bag_Details":"The bag was last seen at MAD on 2019-03-07T13:51:00Z"}
{"Bag_Details":"The bag was last seen at FRA on 2019-03-02T13:18:00Z"}
{"Bag_Details":"The bag was last seen at VIE on 2019-02-12T07:04:00Z"}
{"Bag_Details":"The bag was last seen at JTRJTR on 2019-03-12T15:05:00Z2019-03-12T16:25:00Z"}
{"Bag_Details":"The bag was last seen at JTR on 2019-03-07T16:01:00Z"}
{"Bag_Details":"The bag was last seen at MEL on 2019-02-01T16:13:00Z"}
{"Bag_Details":"The bag was last seen at MXP on 2019-03-22T10:17:00Z"}
{"Bag_Details":"The bag was last seen at MEL on 2019-02-16T16:13:00Z"}
{"Bag_Details":"The bag was last seen at MIA on 2019-03-02T16:09:00Z"}
{"Bag_Details":"The bag was last seen at BZN on 2019-02-21T14:08:00Z"}
{"Bag_Details":"The bag was last seen at SGN on 2019-02-10T10:01:00Z"}
{"Bag_Details":"The bag was last seen at JTR on 2019-02-02T23:59:00Z"}
{"Bag_Details":"The bag was last seen at BLR on 2019-03-14T06:22:00Z"}
{"Bag_Details":"The bag was last seen at VIE on 2019-03-05T12:00:00Z"}
{"Bag_Details":"The bag was last seen at JTR on 2019-03-12T15:05:00Z"}
{"Bag_Details":"The bag was last seen at SEA on 2019-02-15T21:21:00Z"}
{"Bag_Details":"The bag was last seen at HKG on 2019-02-03T08:09:00Z"}
{"Bag_Details":"The bag was last seen at HKG on 2019-02-13T11:15:00Z"}

上に示すように、顧客/予約番号ごとに複数の手荷物が存在する場合、結果は複雑になります。

アプローチ2: この問題に対処するには、次に示すように、bagInfo配列の要素の値として出力します。
SELECT "The bag was last seen at " || [bag.bagInfo[].lastSeenStation] || " on " ||
[bag.bagInfo[].bagArrivalDate] AS Bag_Details FROM BaggageInfo bag

ノート:

列名と静的テキストは、||演算子を使用して連結することもできます。

説明: bagInfo JSON内のドキュメントの一部を様々な静的テキストと連結して、配列の要素として表示します。

出力:
{"Bag_Details":"The bag was last seen at [\"MIA\"] on [\"2019-03-02T16:09:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"BZN\"] on [\"2019-02-21T14:08:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"SGN\"] on [\"2019-02-10T10:01:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"HKG\"] on [\"2019-02-13T11:15:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"JTR\"] on [\"2019-02-02T23:59:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"BLR\"] on [\"2019-03-14T06:22:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"VIE\"] on [\"2019-03-05T12:00:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"JTR\"] on [\"2019-03-12T15:05:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"SEA\"] on [\"2019-02-15T21:21:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"HKG\"] on [\"2019-02-03T08:09:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"BZN\"] on [\"2019-03-15T10:13:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"MEL\"] on [\"2019-02-04T10:08:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"MEL\"] on [\"2019-02-25T20:15:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"MAD\"] on [\"2019-03-07T13:51:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"FRA\"] on [\"2019-03-02T13:18:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"VIE\"] on [\"2019-02-12T07:04:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"JTR\",\"JTR\"] on [\"2019-03-12T15:05:00Z\",
\"2019-03-12T16:25:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"JTR\"] on [\"2019-03-07T16:01:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"MEL\"] on [\"2019-02-01T16:13:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"MXP\"] on [\"2019-03-22T10:17:00Z\"]"}
{"Bag_Details":"The bag was last seen at [\"MEL\"] on [\"2019-02-16T16:13:00Z\"]"}

問合せでの結果のフィルタ処理

WHERE句でフィルタ条件を指定することによって、問合せ結果をフィルタ処理できます。通常、フィルタ条件は、論理演算子ANDまたはORを使用して結合された1つ以上の比較式で構成されます。次の比較演算子もサポートされています: =、!=、>、>=、<および<=。

例1: 特定の予約番号FH7G1Wについて、乗客の手荷物のタグ番号と乗客のフルネームを検索します。
SELECT bag.fullName, bag.bagInfo[].tagNum FROM BaggageInfo bag
WHERE bag.confNo="FH7G1W"

説明: 特定の予約番号に対応するタグ番号をフェッチします。

出力:
{"fullName":"Rosalia Triplett","tagNum":"17657806215913"}

ノート:

理解を深めるために、すべての静的フィールドおよびbagInfo JSONを含むデータ行を次に示します。 
"ticketNo" : 1762344493810,
"fullName" : "Adam Phillips",
"gender" : "M",
"contactPhone" : "893-324-1064",
"confNo" : "LE6J4Z",
 [ {
    "id" : "79039899165297",
    "tagNum" : "17657806255240",
    "routing" : "MIA/LAX/MEL",
    "lastActionCode" : "OFFLOAD",
    "lastActionDesc" : "OFFLOAD",
    "lastSeenStation" : "MEL",
    "flightLegs" : [ {
      "flightNo" : "BM604",
      "flightDate" : "2019-02-01T01:00:00",
      "fltRouteSrc" : "MIA",
      "fltRouteDest" : "LAX",
      "estimatedArrival" : "2019-02-01T03:00:00",
      "actions" : [ {
        "actionAt" : "MIA",
        "actionCode" : "ONLOAD to LAX",
        "actionTime" : "2019-02-01T01:13:00"
      }, {
        "actionAt" : "MIA",
        "actionCode" : "BagTag Scan at MIA",
        "actionTime" : "2019-02-01T00:47:00"
      }, {
        "actionAt" : "MIA",
        "actionCode" : "Checkin at MIA",
        "actionTime" : "2019-02-01T23:38:00"
      } ]
    }, {
      "flightNo" : "BM667",
      "flightDate" : "2019-01-31T22:13:00",
      "fltRouteSrc" : "LAX",
      "fltRouteDest" : "MEL",
      "estimatedArrival" : "2019-02-02T03:15:00",
      "actions" : [ {
        "actionAt" : "MEL",
        "actionCode" : "Offload to Carousel at MEL",
        "actionTime" : "2019-02-02T03:15:00"
      }, {
        "actionAt" : "LAX",
        "actionCode" : "ONLOAD to MEL",
        "actionTime" : "2019-02-01T07:35:00"
      }, {
        "actionAt" : "LAX",
        "actionCode" : "OFFLOAD from LAX",
        "actionTime" : "2019-02-01T07:18:00"
      } ]
    } ],
    "lastSeenTimeGmt" : "2019-02-02T03:13:00",
    "bagArrivalDate" : "2019.02.02T03:13:00"
  } ]
例2: 指定された予約番号FH7G1Wの手荷物は、最後にどこで確認されましたか。また、手荷物のタグ番号もフェッチします。
SELECT bag.fullName, bag.bagInfo[].tagNum,bag.bagInfo[].lastSeenStation
FROM BaggageInfo bag WHERE bag.confNo="FH7G1W"

説明: bagInfoはJSONであり、ドキュメントの配列が移入されます。特定の予約番号について、フルネームと最後に確認されたステーションをフェッチできます。

出力: 
{"fullName":"Rosalia Triplett","tagNum":"17657806215913",
"lastSeenStation":"VIE"}
例3: チケット番号1762340579411の乗客の手荷物の詳細(タグおよび最後に確認された時刻)を選択します。
SELECT bag.ticketNo, bag.fullName, bag.bagInfo[].tagNum,bag.bagInfo[].lastSeenStation
FROM BaggageInfo bag where bag.ticketNo=1762320369957

説明: bagInfoはJSONであり、ドキュメントの配列が移入されます。特定のチケットについて、フルネーム、タグ番号および最後に確認されたステーションをフェッチできます。

出力: 
{"fullName":"Lorenzo Phil","tagNum":["17657806240001","17657806340001"],
"lastSeenStation":["JTR","JTR"]}