Create hive table using “as select” or “like” and also specify delimiter

Question

Is it possible to do a

create table as select

using

row format delimited fields termi         


        

Answer 1

Let's say we have an external table called employee

hive> SHOW CREATE TABLE employee;
OK
CREATE EXTERNAL TABLE employee(
  id string,
  fname string,
  lname string, 
  salary double)
ROW FORMAT SERDE
  'org.apache.hadoop.hive.serde2.lazy.LazySimpleSerDe'
WITH SERDEPROPERTIES (
  'colelction.delim'=':',
  'field.delim'=',',
  'line.delim'='\n',
  'serialization.format'=',')
STORED AS INPUTFORMAT
  'org.apache.hadoop.mapred.TextInputFormat'
OUTPUTFORMAT
  'org.apache.hadoop.hive.ql.io.HiveIgnoreKeyTextOutputFormat'
LOCATION
  'maprfs:/user/hadoop/data/employee'
TBLPROPERTIES (
  'COLUMN_STATS_ACCURATE'='false',
  'numFiles'='0',
  'numRows'='-1',
  'rawDataSize'='-1',
  'totalSize'='0',
  'transient_lastDdlTime'='1487884795')

1. To create a person table like employee

   CREATE TABLE person LIKE employee;

2. To create a person external table like employee

   CREATE TABLE person LIKE employee LOCATION 'maprfs:/user/hadoop/data/person';

3. then use DESC person; to see the newly created table schema.

Answer 2

Create Table as select (CTAS) is possible in Hive.

You can try out below command:

CREATE TABLE new_test 
    row format delimited 
    fields terminated by '|' 
    STORED AS RCFile 
AS select * from source where col=1

1. Target cannot be partitioned table.
2. Target cannot be external table.
3. It copies the structure as well as the data

Create table like is also possible in Hive.

1. It just copies the source table definition.

Answer 3

Both the answers provided above work fine.

1. CREATE TABLE person AS select * from employee;
2. CREATE TABLE person LIKE employee;