select TO_CHAR(ADD_MONTHS(TRUNC(SYSDATE, 'MM'), -3),'YYYY-MM') from v_AreaDataOverYearsFR

这是一个 SQL 查询语句，作用与上一个问题相同，也是获取当前日期往前推三个月的日期（月初），不同的是该语句返回的格式为 'YYYY-MM'，即返回年份和月份的字符串。

具体解释如下：

- TO_CHAR(date, format) 函数用于将日期转换为指定格式的字符串。
- 'YYYY-MM' 表示返回的字符串格式为年份-月份，例如：2021-08。

因此，该语句返回的结果是当前日期往前推三个月的月初日期，并将其转换为年份-月份的字符串格式。

相关问题

SELECT TO_CHAR(ADD_MONTHS(ADD_MONTHS(sysdate, -24), ROWNUM - 1), 'YYYYMM') UNIT_DATE FROM DUAL CONNECT BY ROWNUM <= months_between(sysdate, ADD_MONTHS(sysdate, -24)) 替换成postgre

SELECT to_char(date_trunc('month', (CURRENT_DATE - interval '2 year')::timestamp) + (generate_series(0, date_part('year', age(CURRENT_DATE, (CURRENT_DATE - interval '2 year'))::interval) * 12 + date_part('month', age(CURRENT_DATE, (CURRENT_DATE - interval '2 year'))::interval)) * interval '1 month'), 'YYYYMM') AS UNIT_DATE FROM generate_series(0, date_part('year', age(CURRENT_DATE, (CURRENT_DATE - interval '2 year'))::interval) * 12 + date_part('month', age(CURRENT_DATE, (CURRENT_DATE - interval '2 year'))::interval)) AS t;

SELECT PIS.SHOW_FLT_DETAIL AS SHOW_FLT_DETAIL -- new , PIS.SHOW_AWB_DETAIL AS SHOW_AWB_DETAIL -- new , PIS.DISPLAY_AIRLINE_CODE AS CARRIER_CODE , DECODE(PIS.REVERT_FLOW,'N',PIS.FLOW_TYPE,DECODE(PIS.FLOW_TYPE,'I','E','I')) AS FLOW_TYPE , PIS.SHIP_TO_LOCATION AS SHIP_TO_LOCATION , PIS.INVOICE_SEQUENCE AS INVOICE_SEQUENCE , PFT.FLIGHT_DATE AS FLIGHT_DATE , PFT.FLIGHT_CARRIER_CODE AS FLIGHT_CARRIER_CODE , PFT.FLIGHT_SERIAL_NUMBER AS FLIGHT_SERIAL_NUMBER , PFT.FLOW_TYPE AS AIRCRAFT_FLOW , FAST.AIRCRAFT_SERVICE_TYPE AS AIRCRAFT_SERVICE_TYPE , PPT.AWB_NUMBER AS AWB_NUMBER , PPT.WEIGHT AS WEIGHT , PPT.CARGO_HANDLING_OPERATOR AS CARGO_HANDLING_OPERATOR , PPT.SHIPMENT_PACKING_TYPE AS SHIPMENT_PACKING_TYPE , PPT.SHIPMENT_FLOW_TYPE AS SHIPMENT_FLOW_TYPE , PPT.SHIPMENT_BUILD_TYPE AS SHIPMENT_BUILD_TYPE , PPT.SHIPMENT_CARGO_TYPE AS SHIPMENT_CARGO_TYPE , PPT.REVENUE_TYPE AS REVENUE_TYPE , PFT.JV_FLIGHT_CARRIER_CODE AS JV_FLIGHT_CARRIER_CODE , PPT.PORT_TONNAGE_UID AS PORT_TONNAGE_UID , PPT.AWB_UID AS AWB_UID , PIS.INVOICE_SEPARATION_UID AS INVOICE_SEPARATION_UID , PFT.FLIGHT_TONNAGE_UID AS FLIGHT_TONNAGE_UID FROM PN_FLT_TONNAGES PFT , FZ_AIRLINES FA , PN_TONNAGE_FLT_PORTS PTFP , PN_PORT_TONNAGES PPT , FF_AIRCRAFT_SERVICE_TYPES FAST , SR_PN_INVOICE_SEPARATIONS PIS --new , SR_PN_INVOICE_SEP_DETAILS PISD--new , SR_PN_INV_SEP_PORT_TONNAGES PISPT --new WHERE PFT.FLIGHT_OPERATION_DATE >= trunc( CASE :rundate WHEN TO_DATE('01/01/1900', 'DD/MM/YYYY') THEN ADD_MONTHS(SYSDATE,-1) ELSE ADD_MONTHS(:rundate,-1) END, 'MON') AND PFT.FLIGHT_OPERATION_DATE < trunc( CASE :rundate WHEN TO_DATE('01/01/1900', 'DD/MM/YYYY') THEN TRUNC(SYSDATE) ELSE TRUNC(:rundate) END, 'MON') AND PFT.TYPE IN ('C', 'F') AND PFT.RECORD_TYPE = 'M' AND (PFT.TERMINAL_OPERATOR NOT IN ('X', 'A') OR (PFT.TERMINAL_OPERATOR <> 'X' AND FA.CARRIER_CODE IN (SELECT * FROM SPECIAL_HANDLING_AIRLINE) AND PPT.REVENUE_TYPE IN (SELECT * FROM SPECIAL_REVENUE_TYPE) AND PPT.SHIPMENT_FLOW_TYPE IN (SELECT * FROM SPECIAL_SHIPMENT_FLOW_TYPE) AND PFT.FLIGHT_OPERATION_DATE >= (select EFF_DATE from SPECIAL_HANDLING_EFF_DATE) )) AND PFT.DELETING_DATETIME IS NULL AND FA.AIRLINE_UID = PFT.AIRLINE_UID AND FA.DELETING_DATETIME IS NULL AND PTFP.FLIGHT_TONNAGE_UID = PFT.FLIGHT_TONNAGE_UID AND PTFP.RECORD_TYPE = 'M' AND PTFP.DELETING_DATETIME IS NULL AND PPT.TONNAGE_FLIGHT_PORT_UID (+)= PTFP.TONNAGE_FLIGHT_PORT_UID AND PPT.RECORD_TYPE (+)= 'M' AND PPT.DISCREPANCY_TYPE (+)= 'NONE' AND PPT.ADJUSTMENT_INC_FLAG (+)= 'Y' AND PPT.DELETING_DATETIME (+) IS NULL AND FAST.AIRCRAFT_SERVICE_TYPE_UID = PFT.AIRCRAFT_SERVICE_TYPE_UID AND FAST.DELETING_DATETIME IS NULL AND PIS.TEMPORAL_NAME = TO_CHAR((CASE :rundate --new WHEN TO_DATE('01/01/1900', 'DD/MM/YYYY') THEN TRUNC(SYSDATE) ELSE TRUNC(:rundate) END ), 'YYYYMM') || '00' AND PIS.INVOICE_SEPARATION_UID = PISD.INVOICE_SEPARATION_UID --new AND PISD.INVOICE_SEP_DETAIL_UID = PISPT.INVOICE_SEP_DETAIL_UID --new AND PISPT.PORT_TONNAGE_UID = PPT.PORT_TONNAGE_UID --new AND PIS.PRINT_SUPPORTING_DOC = 'Y';上面是oracle的写法，请转成spark SQL的写法。

以下是转换为 Spark SQL 查询的代码：

SELECT 
    PIS.SHOW_FLT_DETAIL AS SHOW_FLT_DETAIL, 
    PIS.SHOW_AWB_DETAIL AS SHOW_AWB_DETAIL, 
    PIS.DISPLAY_AIRLINE_CODE AS CARRIER_CODE, 
    CASE 
        WHEN PIS.REVERT_FLOW = 'N' THEN PIS.FLOW_TYPE 
        ELSE CASE 
            WHEN PIS.FLOW_TYPE = 'I' THEN 'E' 
            ELSE 'I' 
        END 
    END AS FLOW_TYPE, 
    PIS.SHIP_TO_LOCATION AS SHIP_TO_LOCATION, 
    PIS.INVOICE_SEQUENCE AS INVOICE_SEQUENCE, 
    PFT.FLIGHT_DATE AS FLIGHT_DATE, 
    PFT.FLIGHT_CARRIER_CODE AS FLIGHT_CARRIER_CODE, 
    PFT.FLIGHT_SERIAL_NUMBER AS FLIGHT_SERIAL_NUMBER, 
    PFT.FLOW_TYPE AS AIRCRAFT_FLOW, 
    FAST.AIRCRAFT_SERVICE_TYPE AS AIRCRAFT_SERVICE_TYPE, 
    PPT.AWB_NUMBER AS AWB_NUMBER, 
    PPT.WEIGHT AS WEIGHT, 
    PPT.CARGO_HANDLING_OPERATOR AS CARGO_HANDLING_OPERATOR, 
    PPT.SHIPMENT_PACKING_TYPE AS SHIPMENT_PACKING_TYPE, 
    PPT.SHIPMENT_FLOW_TYPE AS SHIPMENT_FLOW_TYPE, 
    PPT.SHIPMENT_BUILD_TYPE AS SHIPMENT_BUILD_TYPE, 
    PPT.SHIPMENT_CARGO_TYPE AS SHIPMENT_CARGO_TYPE, 
    PPT.REVENUE_TYPE AS REVENUE_TYPE, 
    PFT.JV_FLIGHT_CARRIER_CODE AS JV_FLIGHT_CARRIER_CODE, 
    PPT.PORT_TONNAGE_UID AS PORT_TONNAGE_UID, 
    PPT.AWB_UID AS AWB_UID, 
    PIS.INVOICE_SEPARATION_UID AS INVOICE_SEPARATION_UID, 
    PFT.FLIGHT_TONNAGE_UID AS FLIGHT_TONNAGE_UID 
FROM 
    PN_FLT_TONNAGES PFT 
    JOIN FZ_AIRLINES FA ON FA.AIRLINE_UID = PFT.AIRLINE_UID AND FA.DELETING_DATETIME IS NULL 
    JOIN PN_TONNAGE_FLT_PORTS PTFP ON PTFP.FLIGHT_TONNAGE_UID = PFT.FLIGHT_TONNAGE_UID AND PTFP.RECORD_TYPE = 'M' AND PTFP.DELETING_DATETIME IS NULL 
    LEFT JOIN PN_PORT_TONNAGES PPT ON PPT.TONNAGE_FLIGHT_PORT_UID = PTFP.TONNAGE_FLIGHT_PORT_UID AND PPT.RECORD_TYPE = 'M' AND PPT.DISCREPANCY_TYPE = 'NONE' AND PPT.ADJUSTMENT_INC_FLAG = 'Y' AND PPT.DELETING_DATETIME IS NULL 
    JOIN FF_AIRCRAFT_SERVICE_TYPES FAST ON FAST.AIRCRAFT_SERVICE_TYPE_UID = PFT.AIRCRAFT_SERVICE_TYPE_UID AND FAST.DELETING_DATETIME IS NULL 
    JOIN SR_PN_INVOICE_SEPARATIONS PIS ON PIS.TEMPORAL_NAME = CONCAT(YEAR(:rundate), RIGHT(CONCAT('0', MONTH(:rundate)), 2), '00') AND PIS.INVOICE_SEPARATION_UID = PISD.INVOICE_SEPARATION_UID AND PIS.PRINT_SUPPORTING_DOC = 'Y' 
    JOIN SR_PN_INVOICE_SEP_DETAILS PISD ON PISD.INVOICE_SEP_DETAIL_UID = PISPT.INVOICE_SEP_DETAIL_UID 
    JOIN SR_PN_INV_SEP_PORT_TONNAGES PISPT ON PISPT.PORT_TONNAGE_UID = PPT.PORT_TONNAGE_UID 
WHERE 
    PFT.FLIGHT_OPERATION_DATE >= trunc(CASE 
        WHEN :rundate = TO_DATE('01/01/1900', 'DD/MM/YYYY') THEN ADD_MONTHS(SYSDATE, -1) 
        ELSE ADD_MONTHS(:rundate, -1) 
    END, 'MON') 
    AND PFT.FLIGHT_OPERATION_DATE < trunc(CASE 
        WHEN :rundate = TO_DATE('01/01/1900', 'DD/MM/YYYY') THEN TRUNC(SYSDATE) 
        ELSE TRUNC(:rundate) 
    END, 'MON') 
    AND PFT.TYPE IN ('C', 'F') 
    AND PFT.RECORD_TYPE = 'M' 
    AND (
        PFT.TERMINAL_OPERATOR NOT IN ('X', 'A') 
        OR (
            PFT.TERMINAL_OPERATOR <> 'X' 
            AND FA.CARRIER_CODE IN (SELECT * FROM SPECIAL_HANDLING_AIRLINE) 
            AND PPT.REVENUE_TYPE IN (SELECT * FROM SPECIAL_REVENUE_TYPE) 
            AND PPT.SHIPMENT_FLOW_TYPE IN (SELECT * FROM SPECIAL_SHIPMENT_FLOW_TYPE) 
            AND PFT.FLIGHT_OPERATION_DATE >= (SELECT EFF_DATE FROM SPECIAL_HANDLING_EFF_DATE)
        )
    )
    AND PFT.DELETING_DATETIME IS NULL;

请注意，需要将 `TRUNC` 和 `CONCAT` 函数替换为 Spark SQL 中的相应函数，并使用 `JOIN` 语句替换 `LEFT JOIN` 语句。还需要更改零散的子查询，以便在 Spark SQL 中使用。