I have a parquet file which is stored in a partitioned directory. The format of the partition is
/dates=*/hour=*/something.parquet.
The content of parquet file looks like as follows:
{a:1,b:2,c:3}.
This is json data and i want to create external hive table.
My approach:
CREATE EXTERNAL TABLE test_table (a int, b int, c int) PARTITIONED BY (dates string, hour string) STORED AS PARQUET LOCATION '/user/output/';
After that i run MSCK REPAIR TABLE test_table; but i get following output:
hive> select * from test_table;
OK
NULL NULL NULL 2021-09-27 09
The other three columns are null. I think i have to define JSON schema somehow but i have no idea how to proceed further.
Create table with the same schema as parquet file:
CREATE EXTERNAL TABLE test_table (value string) PARTITIONED BY (dates string, hour string) STORED AS PARQUET LOCATION '/user/output/';
Run repair table to mount partitions:
MSCK REPAIR TABLE test_table;
Parse value in query:
select e.a, e.b, e.c
from test_table t
lateral view json_tuple(t.value, 'a', 'b', 'c') e as a,b,c
Cast values as int if necessary: cast(e.a as int) as a
You can also create a table for json fields as columns using this:
CREATE EXTERNAL TABLE IF NOT EXISTS test_table(
a INT,
b INT,
c INT)
partitioned by (dates string, hour string)
ROW FORMAT SERDE
'org.apache.hive.hcatalog.data.JsonSerDe'
STORED AS PARQUET
location '/user/output/';
Then run MSCK REPAIR TABLE test_table;
You would be able to query directly without writing any parsers.
Related
I have this directory where the data are dumped:
"/externallocation/data/20191123/foo_table/part-00000.orc"
I need to create a external table, pointed to that directory refered above.
The below statement creates the table, but the query not work as expected (no record is returned):
> CREATE EXTERNAL TABLE IF NOT EXISTS foo_table (a_column string, b_column boolean)
PARTITIONED BY (year_month_day_key string)
STORED AS ORC LOCATION '/externallocation/data';
> SELECT * FROM foo_table WHERE year_month_day_key = '20191123';
Could somone now what is wrong. Thanks in advance.
Here is the complete solution -
File already exists on the HDFS directory "/user/hive/warehouse/schema.db/foo_table/year_month_day_key=20191123/000000_0"
Now Create Table
CREATE EXTERNAL TABLE IF NOT EXISTS schema.foo_table
(a_column string,
b_column int)
PARTITIONED BY (year_month_day_key string)
STORED AS ORC
LOCATION 'hdfs://nameservice1/user/hive/warehouse/schema.db/foo_table';
Partition needs to be added after table creation through below Alter command
ALTER TABLE schema.foo_table ADD PARTITION (year_month_day_key = '20191123');
select * from schema.foo_table where year_month_day_key = '20191123';
select * from schema.foo_table;
I have created a table in Hive with the following query:
create table if not exists employee(CASE_NUMBER String,
CASE_STATUS String,
CASE_RECEIVED_DATE DATE,
DECISION_DATE DATE,
EMPLOYER_NAME STRING,
PREVAILING_WAGE_PER_YEAR BIGINT,
PAID_WAGE_PER_YEAR BIGINT,
order_n int) partitioned by (JOB_TITLE_SUBGROUP STRING) row format delimited fields terminated by ',';
I tried loading data into the create table using below query:
LOAD DATA INPATH '/salary_data.csv' overwrite into table employee partition (JOB_TITLE_SUBGROUP);
For the partitioned table, I have even set following configuration :
set hive.exec.dynamic.partition.mode=nonstrict;
set hive.exec.dynamic.partition=true;
But I am getting below error while executing the load query:
Your query has the following error(s):
Error while compiling statement: FAILED: SemanticException org.apache.hadoop.hive.ql.metadata.HiveException: MetaException(message:Invalid partition key & values; keys [job_title_subgroup, ], values [])
Please help.
If you want to load data into a Hive partition, you have to provide the value of the partition itself in the LOAD DATA query. So in this case, your query would be something like this.
LOAD DATA INPATH '/salary_data.csv' overwrite into table employee partition (JOB_TITLE_SUBGROUP="Value");
Where "Value" is the name of the partition in which you are loading your data. The reason is because Hive will use "Value" to create the directory in which your .csv is going to be stored, which will be something like this: .../employee/JOB_TITLE_SUBGROUP=Value. I hope this helps.
Check the documentation for details on the LOAD DATA syntax.
EDITED
Since the table has dynamic partition, one solution would be loading the .csv into an external table (e.g. employee_external) and then execute an INSERT command like this:
INSERT OVERWRITE INTO TABLE employee PARTITION(JOB_TITLE_SUBGROUP)
SELECT CASE_NUMBER, CASE_STATUS, (...), JOB_TITLE_SUBGROUP
FROM employee_external
I might be little late to reply but can try below steps:
Set below properties first :
Ø set hive.exec.dynamic.partition.mode=nonstrict;
Ø set hive.exec.dynamic.partition=true;
Create temp table first:
CREATE EXTERNAL TABLE IF NOT EXISTS employee_temp(
ID STRING,
Name STRING,
Salary STRING)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
LINES TERMINATED BY '\n'
tblproperties ("skip.header.line.count"="1");
Load Data in temporary table:
hive> LOAD DATA INPATH 'filepath/employee.csv' OVERWRITE INTO TABLE employee;
Create Partitioned Table:
CREATE EXTERNAL TABLE IF NOT EXISTS employee_part(
ID STRING,
Name STRING)
PARTITIONED BY (Salary STRING)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
LINES TERMINATED BY '\n'
tblproperties ("skip.header.line.count"="1");
Load Data into partitioned table from intermediate / temp table:
INSERT OVERWRITE TABLE employee_part PARTITION (SALARY) SELECT * FROM employee;
i have a Text Format hive table, like:
CREATE EXTERNAL TABLE op_log (
time string, debug string,app_id string,app_version string, ...more fields)
PARTITIONED BY (dt string)
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t'
STORED AS TEXTFILE;
now i create a orc format table with same fields, like
CREATE TABLE op_log_orc (
time string, debug string,app_id string,app_version string, ...more fields)
PARTITIONED BY (dt string)
STORED AS ORC tblproperties ("orc.compress" = "SNAPPY");
when i copy from op_log to op_log_orc, i have get this errors:
hive> insert into op_log_orc PARTITION(dt='2016-08-09') select * from op_log where dt='2016-08-09';
FAILED: SemanticException [Error 10044]: Line 1:12 Cannot insert into target table because column number/types are different ''2016-08-09'': Table insclause-0 has 62 columns, but query has 63 columns.
hive>
The partition key (dt) in the source table is returned in the result set as though it were a regular field, so you have the extra column. Exclude the dt field from the field list (instead of *) if you're going to specify its value in the partition key. Alternatively, just specify dt as the name of the partition, without providing a value. See CTAS (create table as select...) in the example here: https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DDL#LanguageManualDDL-CreateTableAsSelect(CTAS)
First i created hive external table partitioned by code and date
CREATE EXTERNAL TABLE IF NOT EXISTS XYZ
(
ID STRING,
SAL BIGINT,
NAME STRING,
)
PARTITIONED BY (CODE INT,DATE STRING)
ROW FORMAT SERDE 'parquet.hive.serde.ParquetHiveSerDe'
STORED AS
INPUTFORMAT "parquet.hive.DeprecatedParquetInputFormat"
OUTPUTFORMAT "parquet.hive.DeprecatedParquetOutputFormat"
LOCATION '/old_work/XYZ';
and then i execute insert overwrite on this table taking data from other table
INSERT OVERWRITE TABLE XYZ PARTITION (CODE,DATE)
SELECT
*
FROM TEMP_XYZ;
and after that i count the number of records in hive
select count(*) from XYZ;
it shows me 1000 records are there
and then i rename or move the location '/old_work/XYZ' to '/new_work/XYZ'
and then i again drop the XYZ table and created again pointing location to new directory
means '/new_work/XYZ'
CREATE EXTERNAL TABLE IF NOT EXISTS XYZ
(
ID STRING,
SAL BIGINT,
NAME STRING,
)
PARTITIONED BY (CODE INT,DATE STRING)
ROW FORMAT SERDE 'parquet.hive.serde.ParquetHiveSerDe'
STORED AS
INPUTFORMAT "parquet.hive.DeprecatedParquetInputFormat"
OUTPUTFORMAT "parquet.hive.DeprecatedParquetOutputFormat"
LOCATION '/new_work/XYZ';
But then when i execute select count(*) from XYZ table in hive , it shows 0 records ,
i think i missed something , please help me on this????
You need not drop the table and re create it the second time:
As soon as you move or rename a external hdfs location of the table just do this :
msck repair table <table_name>
In your case the error was because, The hive metastore wasnt updated with the new path .
I have loaded the data into hive table from the notepad, it is showing data is copied but when i run the select query it is showing null, please let us know what could be the reason
hive> create table test_sq(k string, v string) stored as sequencefile;
hive> load data local inpath '/tmp/input.txt' into table test_sq;
OK
hive> select * from tesst_t;
OK
NULL NULL
NULL NULL
Notepad : Assuming it is text. Whereas you have specified it as sequencefile.
Your create table script should be:
create table test_sq(k string, v string) row format delimited fields terminated by '';
I m not sure, if it is just a typo but you are trying to query on other table (tesst_t) instead of table that you loaded (test_sq)
Can you provide a sample line from your text file.
If you are using tab as delimiter then you can just use create table test_sq(k string, v string); .In other cases , as venkat has mentioned , use create table test_sq(k string, v string) row format delimited fields terminated by 'single_character_delimiter' . This will work even with tab delimiter('\t').