#修改分隔符
alter table firstround.person_aaa_crime_criminalperson1 set SERDEPROPERTIES('field.delim'='\001');
#查看建表语句
show CREATE TABLE firstround.banklog_decrypt
#修改字段类型
ALTER TABLE data_market.last_process_time CHANGE hive_count_num hive_count_num string
#更改表名
ALTER TABLE transfer_sjdk.bigdata_blacklist RENAME TO transfer_sjdk.tbl_riskprice_it;
#添加表字段
ALTER TABLE transfer_sjdk.bigdata_blacklist_history ADD COLUMNS (is_black string);
#删除表字段
ALTER TABLE transfer_sjdk.bigdata_blacklist_history drop is_black;
#清除表数据
TRUNCATE transfer_sjdk.tbl_riskprice_it;
#刷新表
REFRESH transfer_sjdk.tbl_riskprice_it;
#刷新表元数据
INVALIDATE METADATA transfer_sjdk.tbl_riskprice_it;
#重新shuffle数据
INSERT OVERWRITE data_market.repayment_split_table SELECT * FROM data_market.repayment_split_table;
#复制表结果和数据
create table transfer_zhifu_real.sy_role as select * from transfer_zhifu.sy_role;
#复制表结构
create table transfer_zhifu_real.sy_role like transfer_zhifu.sy_role;
#修改表名
ALTER TABLE dh_0016_bigdata_08 RENAME TO dh_0016_bigdata
#修改表字段类型
alter TABLE users CHANGE dt dt string
#显示所有函数
show functions;
#查看函数用法(hive)
describe function substr;
#导出查询结果到文件
impala-shell -q "select * from table limit 10" -B --output_delimiter="\t" -o output.txt
#收集表的统计信息,让Impala 基于每一个表的大小、每一个列不同值的个数、等等信息自动的优化查询。
compute stats firstround.person_aaa_crime_escapeperson;
#导入和导出
export table poc.chan_info to '/user/hive/test/chan_info';
import from '/user/hive/test/chan_info';
#分区表导出和导入
export table poc.cust_basic_info partition (etl_dt="2017-12-14") to '/user/hive/test/cust_basic_info14';
import from '/user/hive/test/cust_basic_info14';
#import重命名表
import table cust_basic_info from '/user/hive/test/cust_basic_info14';
#导出表并且导入到分区表分区
import table cust_basic_info partition (etl_dt="2017-12-14") from '/user/hive/test/cust_basic_info';
#指定导入位置
import table cust_basic_info from '/user/hive/test/cust_basic_info' location '/user/hive/test/cust_basic_info';
#导入作为一个外部表
import external table cust_basic_info from '/user/hive/test/cust_basic_info';
#强制删除数据库
DROP DATABASE zxfinance_alpha1_tuomin cascade
#数据类型转换
SELECT cast(substr(createdate,1,10) as int)/86400 created FROM frontlog
#分组排序
row_number() over (PARTITION BY t4.extractcashbillid,t1.ze_checktime ORDER BY t4.overduedateb DESC) flag
除Row_number外还有rank,dense_rank
rank() over([partition by col1] order by col2)
dense_rank() over([partition by col1] order by col2)
row_number() over([partition by col1] order by col2)
rank排序时出现相等的值时会有并列，即值相等的两条数据会有相同的序列值
row_number的排序不允许并列，即使两条记录的值相等也不会出现相等的排序值
dense_rank排序的值允许并列，但会跳跃的排序，像这样：1,1,3,4,5,5,7.
#添加udf 方法
impala-shell -q "create function AES(string) returns string location '/user/hive/udf/aesUDF.jar' symbol='com.netease.hive.udf.AESUDF';"
#创建分区表
CREATE TABLE IF NOT EXISTS asset_auxiliary.dh_0016_bigdata_history(
autoindex INT, vindicatorteamid STRING,
createtime STRING)
PARTITIONED BY (dt string) ROW FORMAT DELIMITED FIELDS TERMINATED BY '\001' STORED AS TEXTFILE;
#添加分区
alter table asset_auxiliary.dh_0016_bigdata_history add partition (dt='2017-12-12');
#删除分区
ALTER TABLE asset_auxiliary.dh_0016_bigdata_history DROP IF EXISTS PARTITION(dt='2017-12-12');
#加载数据
LOAD DATA INPATH ‘/user/hive/warehouse/asset_auxiliary.db/dh_0016_bigdata_history/2017-12-12/000000_0’ INTO TABLE asset_auxiliary.dh_0016_bigdata_history PARTITION(dt='2017-12-12');
#加载数据到hdfs(hive)
insert overwrite directory '/user/hive/warehouse/asset_auxiliary.db/dh_0016_bigdata_history/dt=2017-12-12'
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\001'
select * from asset_auxiliary.dh_0016_bigdata_tmp where queryday = '2017-12-12'
#加载数据到本地(hive)
insert overwrite local directory '/data/2017-12-12'
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\001'
select * from asset_auxiliary.dh_0016_bigdata_tmp where queryday = '2017-12-12'
#插入数据到表分区
insert into table asset_auxiliary.dh_0016_bigdata_history PARTITION(dt='2017-12-10') select * from asset_auxiliary.dh_0016_bigdata_tmp where queryday = '2017-12-10'
#展示表中有多少分区
show partitions asset_auxiliary.dh_0016_bigdata_history;
#刷新分区
REFRESH asset_auxiliary.dh_0016_bigdata PARTITION(dt='2017-12-12');
#修复表分区 （hive）
msck repair table 表名
#hive 建表
create table test_label.user_json
(
userid string,
accountid string,
banknumber string,
bankname string,
isreceiveaccount string,
isrepayaccount string,
birthday string,
createtime string
)
comment '用户大宽表'
partitioned by(createtime string comment '时间分区字段')
row format delimited
fields terminated by '\t'
stored as textfile location '/user/hdfs/fico/output/1491964346/user_back_json/';
###impala查询内存限制Memory limit exceeded
ERROR:
Memory limit exceeded
Query did not have enough memory to get the minimum required buffers in the block manager.
mem_limit=-1
default_pool_mem_limit=-1b
note:https://blog.csdn.net/oosongoo/article/details/78435779