我正在尝试使用(选择,加入(查询将数据添加到 Impala 中的新列,一旦将数据添加到新列,我就会丢失所有其他列的数据(它们变为 NULL(。
在这里,我创建第一个表:
CREATE TABLE mng_exp.KPI_LATENCE_JOUR
(
CODEINSEE INT,
IMEI BIGINT,
SEMAINE INT,
MOYENNE_LATENCE INT,
MAXIMUM_LATENCE INT,
MINIMUM_LATENCE INT
)
我将数据添加到表中:
INSERT INTO mng_exp.KPI_LATENCE_JOUR (CODEINSEE,IMEI, SEMAINE, MOYENNE_LATENCE,MAXIMUM_LATENCE,MINIMUM_LATENCE,TRANCHE_DE_LATENCE)
SELECT codeinsee, device_dim__imei as IMEI,weekofyear(jour) as SEMAINE, cast(round(avg(rtt_avg_ms)) as integer) as MOYENNE_LATENCE,
cast(round(avg(rtt_max_ms)) as integer) as MAXIMUM_LATENCE, cast(round(avg(rtt_min_ms)) as integer) as MINIMUM_LATENCE ,
CASE WHEN ( round(avg(rtt_avg_ms)) > 0 and round(avg(rtt_avg_ms)) <= 10 ) THEN 0
WHEN ( round(avg(rtt_avg_ms)) > 10 and round(avg(rtt_avg_ms)) <= 20 ) THEN 1
WHEN ( round(avg(rtt_avg_ms)) > 20 and round(avg(rtt_avg_ms)) <= 30 ) THEN 2
WHEN ( round(avg(rtt_avg_ms)) > 30 ) THEN 3 END AS Tranche_de_latence
FROM mscore.mscore where operateur = 'BT_HZ' and year(jour) = 2019 group by device_dim__imei,weekofyear(jour),codeinsee
# I Add a new column
ALTER TABLE mng_exp.kpi_latence_jour ADD COLUMNS (srv_id BIGINT)
#Here data is good and new column srv_id is NULL
我将数据添加到新列:
INSERT INTO mng_exp.KPI_LATENCE_jour (srv_id)
SELECT CAST(dng_fai_cli_eqt_iad.srv_id AS BIGINT)
FROM msf_exploratoire.dng_fai_cli_eqt_iad
INNER JOIN mng_exp.kpi_latence_jour ON (dng_fai_cli_eqt_iad.num_serie = kpi_latence_jour.imei);
问题是:srv_id
正常,旧列变为 NULL。
我没有查询错误,但我丢失了所有旧数据
您只插入一列。使用插入覆盖并添加所有其他列:
INSERT OVERWRITE TABLE mng_exp.KPI_LATENCE_jour (CODEINSEE,IMEI, SEMAINE, MOYENNE_LATENCE,MAXIMUM_LATENCE,MINIMUM_LATENCE,TRANCHE_DE_LATENCE,srv_id)
SELECT b.CODEINSEE,
b.IMEI,
b.SEMAINE,
b.MOYENNE_LATENCE,
b.MAXIMUM_LATENCE,
b.MINIMUM_LATENCE,
b.TRANCHE_DE_LATENCE,
CAST(a.srv_id AS BIGINT) srv_id
FROM msf_exploratoire.dng_fai_cli_eqt_iad a
INNER JOIN mng_exp.kpi_latence_jour b ON (a.num_serie = b.imei)
;
您确定丢失了所有旧数据还是执行:
select * from mng_exp.KPI_LATENCE_JOUR
您还将看到:
- 第一组行(srv_id为 null 的行(;
- 第二组行 - 唯一填充的列srv_id的行?
您想要的是更新第一组行的SRV_ID。
您可以在此处查看有关 imapala更新的更多详细信息。