Update column in HIVE - hive

I have a table in php which is in this format:
CREATE EXTERNAL TABLE IF NOT EXISTS {$tableName} (fileContent VARCHAR(250), description VARCHAR(250), dimension DOUBLE, fileName VARCHAR(250)) ROW FORMAT
DELIMITED FIELDS TERMINATED BY ','
LINES TERMINATED BY '\n'
STORED AS TEXTFILE
LOCATION '/var/www/ASOIS_Proiect/metadata/'
I want for a situation to update only description field if fileName='a' and 'size'='12' already exist in database.
Any idea please? I tried to update the file create for insert with command LOAD and flag OVERWRITE but it is not working.

Related

How to handle the embedded commas in hive?

For example if I have a csv file with three cols,
sno,name,salary
1,latha, 2000
2,Bhavish, Chaturvedi, 3000
How to load this type of file in hive. I tried few of the posts from stackoverflow, but it didn't worked.
I have created a external table:
create external table test(
id int,
name string,
salary int
)
fields terminated by '\;'
stored as text file;
and loaded the data into it.
But when done select * from table, I got all null's into it.
I think CSV file has column name then you have to skip header to avoid the error follow the following steps:
Step 1: Create table e.g
CREATE TABLE salary (sno INT, name STRING, salary INT)
row format delimited fields terminated BY ',' stored as textfile
tblproperties("skip.header.line.count"="1");
Step 2: load the CSV file into table e.g
load data local inpath 'file path' into table salary;
Step 3: Test the records
select * from salary;

error loading csv into hive table

I'm trying to load a tab delimited file into a table in hive, and I want to skip the first row because it contains column names. I'm trying to run the code below, but I'm getting the error below. Does anyone see what the issue is?
Code:
set hive.exec.compress.output=false;
set hive.mapred.mode=nonstrict;
-- region to state mapping
DROP TABLE IF EXISTS StateRegion;
CREATE TEMPORARY TABLE StateRegion (Zip_Code int,
Place_Name string,
State string,
State_Abbreviate string,
County string,
Latitude float,
Longitude float,
ZIP_CD int,
District_NM string,
Region_NM string)
row format delimited fields terminated by '\t'
tblproperties("skip.header.line.count"="1");
STORED AS TEXTFILE;
LOAD DATA LOCAL INPATH 'StateRegion'
OVERWRITE INTO TABLE StateRegion;
--test Export
INSERT OVERWRITE LOCAL DIRECTORY './StateRegionTest/'
ROW FORMAT DELIMITED FIELDS TERMINATED BY '\t'
select * from StateRegion;
Error:
FAILED: ParseException line 2:0 cannot recognize input near 'STORED' 'AS' 'TEXTFILE'

How to create an external Hive table if the field value has comma separated values

I had used sqoop-import command to sqoop the data into Hive from teradata. Sqoop-import command is creating a text file with comma(,) as the delimiter.
After Sqooping, I had created an external table as shown below:
CREATE EXTERNAL TABLE IF NOT EXISTS employee ( eid int, name String,
salary String, description String)
COMMENT ‘Employee details’
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ‘,’
LINES TERMINATED BY ‘\n’
STORED AS TEXTFILE;
But description column has values like this:"abc,xyz,mnl". Due to this,loading of data into a hive table is not proper. Then how to create a text file with a delimiter other than comma while sqooping.
Then how to delimit the fields while creating an external table of Hive?
Use --fields-terminated-by in your Sqoop job if you want to avoid the default delimiter.
--fields-terminated-by - This parameter is used for field separator character in output.
Example: --fields-terminated-by |
and then change fields separator in create table statement by FIELDS TERMINATED BY ‘|’

Hive: Partitioning by part of integer column

I want to create an external Hive table, partitioned by record type and date (year, month, day). One complication is that the date format I have in my data files is a single value integer yyyymmddhhmmss instead of the required date format yyyy-mm-dd hh:mm:ss.
Can I specify 3 new partition column based on just single data value? Something like the example below (which doesn't work)
create external table cdrs (
record_id int,
record_detail tinyint,
datetime_start int
)
partitioned by (record_type int, createyear=datetime_start(0,3) int, createmonth=datetime_start(4,5) int, createday=datetime_start(6,7) int)
row format delimited
fields terminated by '|'
lines terminated by '\n'
stored as TEXTFILE
location 'hdfs://nameservice1/tmp/sbx_unleashed.db'
tblproperties ("skip.header.line.count"="1", "skip.footer.line.count"="1");
If you want to be able to use MSCK REPAIR TABLE to add the partition for you based on the directories structure you should use the following convention:
The nesting of the directories should match the order of the partition columns.
A directory name should be {partition column name}={value}
If you intends to add the partitions manually then the structure has no meaning.
Any set values can be coupled with any directory. e.g. -
alter table cdrs
add if not exist partition (record_type='TYP123',createdate=date '2017-03-22')
location 'hdfs://nameservice1/tmp/sbx_unleashed.db/2017MAR22_OF_TYPE_123';
Assuming directory structure -
.../sbx_unleashed.db/record_type=.../createyear=.../createmonth=.../createday=.../
e.g.
.../sbx_unleashed.db/record_type=TYP123/createyear=2017/createmonth=03/createday=22/
create external table cdrs
(
record_id int
,record_detail tinyint
,datetime_start int
)
partitioned by (record_type int,createyear int, createmonth tinyint, createday tinyint)
row format delimited
fields terminated by '|'
lines terminated by '\n'
stored as TEXTFILE
location 'hdfs://nameservice1/tmp/sbx_unleashed.db'
tblproperties ("skip.header.line.count"="1", "skip.footer.line.count"="1")
;
Assuming directory structure -
.../sbx_unleashed.db/record_type=.../createdate=.../
e.g.
.../sbx_unleashed.db/record_type=TYP123/createdate=2017-03-22/
create external table cdrs
(
record_id int
,record_detail tinyint
,datetime_start int
)
partitioned by (record_type int,createdate date)
row format delimited
fields terminated by '|'
lines terminated by '\n'
stored as TEXTFILE
location 'hdfs://nameservice1/tmp/sbx_unleashed.db'
tblproperties ("skip.header.line.count"="1", "skip.footer.line.count"="1")
;

Adding a comma separated table to Hive

I have a very basic question which is: How can I add a very simple table to Hive. My table is saved in a text file (.txt) which is saved in HDFS. I have tried to create an external table in Hive which points out this file but when I run an SQL query (select * from table_name) I don't get any output.
Here is an example code:
create external table Data (
dummy INT,
account_number INT,
balance INT,
firstname STRING,
lastname STRING,
age INT,
gender CHAR(1),
address STRING,
employer STRING,
email STRING,
city STRING,
state CHAR(2)
)
LOCATION 'hdfs:///KibTEst/Data.txt';
KibTEst/Data.txt is the path of the text file in HDFS.
The rows in the table are seperated by carriage return, and the columns are seperated by commas.
Thanks for your help!
You just need to create an external table pointing to your file
location in hdfs and with delimiter properties as below:
create external table Data (
dummy INT,
account_number INT,
balance INT,
firstname STRING,
lastname STRING,
age INT,
gender CHAR(1),
address STRING,
employer STRING,
email STRING,
city STRING,
state CHAR(2)
)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
LINES TERMINATED BY '\n'
LOCATION 'hdfs:///KibTEst/Data.txt';
You need to run select query(because file is already in HDFS and external table directly fetches data from it when location is specified in create statement). So you test using below select statement:
SELECT * FROM Data;
create external table Data (
dummy INT,
account_number INT,
balance INT,
firstname STRING,
lastname STRING,
age INT,
gender CHAR(1),
address STRING,
employer STRING,
email STRING,
city STRING,
state CHAR(2)
)
row format delimited
FIELDS TERMINATED BY ‘,’
stored as textfile
LOCATION 'Your hdfs location for external table';
If data in HDFS then use :
LOAD DATA INPATH 'hdfs_file_or_directory_path' INTO TABLE tablename
The use select * from table_name
create external table Data (
dummy INT,
account_number INT,
balance INT,
firstname STRING,
lastname STRING,
age INT,
gender CHAR(1),
address STRING,
employer STRING,
email STRING,
city STRING,
state CHAR(2)
)
row format delimited
FIELDS TERMINATED BY ','
stored as textfile
LOCATION '/Data';
Then load file into table
LOAD DATA INPATH '/KibTEst/Data.txt' INTO TABLE Data;
Then
select * from Data;
I hope, below inputs will try to answer the question asked by #mshabeen.
There are different ways that you can use to load data in Hive table that is created as external table.
While creating the Hive external table you can either use the LOCATION option and specify the HDFS, S3 (in case of AWS) or File location, from where you want to load data OR you can use LOAD DATA INPATH option to load data from HDFS, S3 or File after creating the Hive table.
Alternatively you can also use ALTER TABLE command to load data in the Hive partitions.
Below are some details
Using LOCATION - Used while creating the Hive table. In this case data is already loaded and available in Hive table.
**LOAD DATA INPATH** option - This Hive command can be used to load data from specified location. Point to remember here is, the data will get MOVED from input path to Hive warehouse path.
Example -
LOAD DATA INPATH 'hdfs://cluster-ip/path/to/data/location/'
Using ALTER TABLE command - Mostly this is used to add data from other locations into the Hive partitions. In this case it is required that all partitions are already defined and the values for the partitions are already known. In case of dynamic partitions this command is not required.
Example -
ALTER TABLE table_name ADD PARTITION (date_col='2018-02-21') LOCATION 'hdfs/path/to/location/'
The above code will map the partition to the specified data location (in this case HDFS). However, the data will NOT MOVED to Hive internal warehouse location.
Additional details are available here