I am trying to get the current date into a Hive database (version 0.13 running on an HDInsight cluster) with the following script
SET curdt = from_unixtime(unix_timestamp());
DROP TABLE IF EXISTS curtime_test;
CREATE TABLE curtime_test (
dateEntered STRING
);
INSERT INTO TABLE curtime_test
SELECT '${hivevar:curdt}' FROM hivesampletable limit 3;
SELECT * FROM curtime_test;
Note that I want to have the same insert date for all the inserted records, this is a toy example, but the real one I want to use it on has millions of records to insert. This version I tried above just inserts the string '${hivevar:curdt}' into the database, which is not what I want:
${hivevar:curdt}
${hivevar:curdt}
${hivevar:curdt}
Omitting the quotes causes the insert to error out because of the spaces in the string. How can I do this right?
Update:
Using the line
SELECT ${hiveconf:curdt} FROM hivesampletable limit 3;
as per the comment from Charlie Haley (I mixed up ${hivevar} and ${hiveconf}), gives me the results that I want. If he writes it up as an answer I will mark it as right.
The following code sample works for me. Does this solve your problem?
DROP TABLE IF EXISTS curtime_test;
CREATE TABLE curtime_test (
dateEntered STRING
);
INSERT INTO TABLE curtime_test
SELECT unix_timestamp() FROM hivesampletable limit 1;
SELECT * FROM curtime_test;
SQLite 3.8.3 added support for CTEs. I tried some of the sample CTEs on this page and they work fine. However, after reading the documentation and trying to adapt some of the examples I am unable to create a simple test.
First, I create a simple table with two fields: id and parent. This will create a simple tree or linked list of records:
CREATE TABLE test(id INTEGER PRIMARY KEY ASC,parent INTEGER);
Now I populate it with a few rows:
INSERT INTO test (parent) VALUES (NULL);
INSERT INTO test (parent) VALUES (1);
INSERT INTO test (parent) VALUES (2);
INSERT INTO test (parent) VALUES (3);
After which I have a table that looks like this:
---+-------
id | parent
---+-------
1 | NULL
2 | 1
3 | 2
4 | 3
Now I want to generate a list of rows along the path between 3 and 1:
WITH RECURSIVE test1(id,parent) AS (
VALUES(3,2)
UNION ALL
SELECT * FROM test WHERE test.parent=test1.id)
SELECT * FROM test1;
But I get the error:
no such column: test1.id
Both test and test1 have an id field, so why does it claim it does not exist? I have reviewed the documentation several times and don't see my mistake. What am I doing wrong?
It is necessary to include the test1 table in the SELECT:
WITH RECURSIVE test1(id,parent) AS (
VALUES(3,2)
UNION ALL
SELECT test.id,test.parent FROM test,test1 WHERE test1.parent=test.id)
SELECT * FROM test1;
Note that the WHERE clause has been reversed, the original test in the question returns from the current row to the end, rather than from the end back to the start.
I am new to hive. I just wanted to know how I can insert data into Hive table directly
Create table t1 ( name string)
and I want to insert a value eg name = 'John'
But I have seen so many documentation there isn't any example that inserts data directly into the table. Either I need to create a file internal or externally and add the value 'John' and load this data into the table or i can load data from another table.
My goal is to add data directly into the hive table by providing a values directly? I have provided an oracle example of a sql query I want to achieve:
INSERT INTO t1 (name)
values ('John')
I want an equivalent statement as above in Hive ?
You can use hive's table generating functions,like exlode() or stack()
Example
Table struct as (name String, age Int)
INSERT INTO TABLE target_table
SELECT STACK(
2, # Amount of record
'John', 80, # record 1
'Bill', 61 # record 2
)
FROM dual # Any table already exists
LIMIT 2; # Amount of record! Have to add this line!
That will add 2 records in your target_table.
As of latest version of Hive, insert into .. values (...)is not supported. The enhancement to insert/update/delete syntax is under development. Please look at the Implement insert, update, and delete in Hive with full ACID support
Inserting values into a table is now supported by HIVE from the version Hive 0.14.
CREATE TABLE students (name VARCHAR(64), age INT, gpa DECIMAL(3, 2)) CLUSTERED BY (age) INTO 2 BUCKETS STORED AS ORC;
INSERT INTO TABLE students VALUES ('fred flintstone', 35, 1.28), ('barney rubble', 32, 2.32);
More can be found at https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DML#LanguageManualDML-InsertingvaluesintotablesfromSQL
I am new to hive, and want to know if there is anyway to insert data into Hive table like we do in SQL. I want to insert my data into hive like
INSERT INTO tablename VALUES (value1,value2..)
I have read that you can load the data from a file to hive table or you can import data from one table to hive table but is there any way to append the data as in SQL?
Some of the answers here are out of date as of Hive 0.14
https://cwiki.apache.org/confluence/display/Hive/LanguageManual+DML#LanguageManualDML-InsertingvaluesintotablesfromSQL
It is now possible to insert using syntax such as:
CREATE TABLE students (name VARCHAR(64), age INT, gpa DECIMAL(3, 2));
INSERT INTO TABLE students
VALUES ('fred flintstone', 35, 1.28), ('barney rubble', 32, 2.32);
You can use the table generating function stack to insert literal values into a table.
First you need a dummy table which contains only one line. You can generate it with the help of limit.
CREATE TABLE one AS
SELECT 1 AS one
FROM any_table_in_your_database
LIMIT 1;
Now you can create a new table with literal values like this:
CREATE TABLE my_table AS
SELECT stack(3
, "row1", 1
, "row2", 2
, "row3", 3
) AS (column1, column2)
FROM one
;
The first argument of stack is the number of rows you are generating.
You can also add values to an existing table:
INSERT INTO TABLE my_table
SELECT stack(2
, "row4", 1
, "row5", 2
) AS (column1, column2)
FROM one
;
Slightly better version of the unique2 suggestion is below:
insert overwrite table target_table
select * from
(
select stack(
3, # generating new table with 3 records
'John', 80, # record_1
'Bill', 61 # record_2
'Martha', 101 # record_3
)
) s;
Which does not require the hack with using an already exiting table.
You can use below approach. With this, You don't need to create temp table OR txt/csv file for further select and load respectively.
INSERT INTO TABLE tablename SELECT value1,value2 FROM tempTable_with_atleast_one_records LIMIT 1.
Where tempTable_with_atleast_one_records is any table with atleast one record.
But problem with this approach is that If you have INSERT statement which inserts multiple rows like below one.
INSERT INTO yourTable values (1 , 'value1') , (2 , 'value2') , (3 , 'value3') ;
Then, You need to have separate INSERT hive statement for each rows. See below.
INSERT INTO TABLE yourTable SELECT 1 , 'value1' FROM tempTable_with_atleast_one_records LIMIT 1;
INSERT INTO TABLE yourTable SELECT 2 , 'value2' FROM tempTable_with_atleast_one_records LIMIT 1;
INSERT INTO TABLE yourTable SELECT 3 , 'value3' FROM tempTable_with_atleast_one_records LIMIT 1;
No. This INSERT INTO tablename VALUES (x,y,z) syntax is currently not supported in Hive.
You could definitely append data into an existing table. (But it is actually not an append at the HDFS level). It's just that whenever you do a LOAD or INSERT operation on an existing Hive table without OVERWRITE clause the new data will be put without replacing the old data. A new file will be created for this newly inserted data inside the directory corresponding to that table. For example :
I have a file named demo.txt which has 2 lines :
ABC
XYZ
Create a table and load this file into it
hive> create table demo(foo string);
hive> load data inpath '/demo.txt' into table demo;
Now,if I do a SELECT on this table it'll give me :
hive> select * from demo;
OK
ABC
XYZ
Suppose, I have one more file named demo2.txt which has :
PQR
And I do a LOAD again on this table without using overwrite,
hive> load data inpath '/demo2.txt' into table demo;
Now, if I do a SELECT now, it'll give me,
hive> select * from demo;
OK
ABC
XYZ
PQR
HTH
Ways to insert data into Hive table:
for demonstration, I am using table name as table1 and table2
create table table2 as select * from table1 where 1=1;
or
create table table2 as select * from table1;
insert overwrite table table2 select * from table1;
--it will insert data from one to another. Note: It will refresh the target.
insert into table table2 select * from table1;
--it will insert data from one to another. Note: It will append into the target.
load data local inpath 'local_path' overwrite into table table1;
--it will load data from local into the target table and also refresh the target table.
load data inpath 'hdfs_path' overwrite into table table1;
--it will load data from hdfs location iand also refresh the target table.
or
create table table2(
col1 string,
col2 string,
col3 string)
row format delimited fields terminated by ','
location 'hdfs_location';
load data local inpath 'local_path' into table table1;
--it will load data from local and also append into the target table.
load data inpath 'hdfs_path' into table table1;
--it will load data from hdfs location and also append into the target table.
insert into table2 values('aa','bb','cc');
--Lets say table2 have 3 columns only.
Multiple insertion into hive table
Yes you can insert but not as similar to SQL.
In SQL we can insert the row level data, but here you can insert by fields (columns).
During this you have to make sure target table and the query should have same datatype and same number of columns.
eg:
CREATE TABLE test(stu_name STRING,stu_id INT,stu_marks INT)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
STORED AS TEXTFILE;
INSERT OVERWRITE TABLE test SELECT lang_name, lang_id, lang_legacy_id FROM export_table;
To insert entire data of table2 in table1. Below is a query:
INSERT INTO TABLE table1 SELECT * FROM table2;
You can't do insert into to insert single record. It's not supported by Hive. You may place all new records that you want to insert in a file and load that file into a temp table in Hive. Then using insert overwrite..select command insert those rows into a new partition of your main Hive table. The constraint here is your main table will have to be pre partitioned. If you don't use partition then your whole table will be replaced with these new records.
Enter the following command to insert data into the testlog table with some condition:
INSERT INTO TABLE testlog SELECT * FROM table1 WHERE some condition;
I think in such scenarios you should be using HBASE which facilitates such kind of insertion but it does not provide any SQL kind of query language. You need you use Java API of HBASE like the put method to do such kind of insertion. Moreover HBASE is column oriented no-sql database.
You still can insert into complex type in Hive - it works
(id is int, colleagues array)
insert into emp (id,colleagues) select 11, array('Alex','Jian') from (select '1')
you can add values to specific columns as well, just specify the column names in which you like to add corresponding values:
Insert into Table (Col1, Col2, Col4,col5,Col7) Values ('Va11','Va2','Val4','Val5','Val7');
Make sure the columns you skip dont have not null value type.
There are few properties to set to make a Hive table support ACID properties and to insert the values into tables as like in SQL .
Conditions to create a ACID table in Hive.
The table should be stored as ORC file. Only ORC format can support ACID prpoperties for now.
The table must be bucketed
Properties to set to create ACID table:
set hive.support.concurrency =true;
set hive.enforce.bucketing =true;
set hive.exec.dynamic.partition.mode =nonstrict
set hive.compactor.initiator.on = true;
set hive.compactor.worker.threads= 1;
set hive.txn.manager = org.apache.hadoop.hive.ql.lockmgr.DbTxnManager;
set the property hive.in.test to true in hive.site.xml
After setting all these properties , the table should be created with tblproperty 'transactional' ='true'. The table should be bucketed and saved as orc
CREATE TABLE table_name (col1 int,col2 string, col3 int) CLUSTERED BY col1 INTO 4
BUCKETS STORED AS orc tblproperties('transactional' ='true');
Now its possible to inserte values into the table like SQL query.
INSERT INTO TABLE table_name VALUES (1,'a',100),(2,'b',200),(3,'c',300);
Yes we can use Insert query in Hive.
hive> create table test (id int, name string);
INSERT: INSERT...VALUES is available starting in version 0.14.
hive> insert into table test values (1,'mytest');
This is going to work for insert. We have to use values keyword.
Note: User cannot insert data into a complex datatype column (array, map, struct, union) using the INSERT INTO...VALUES clause.