[ https://issues.apache.org/jira/browse/HIVE-13812?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Takahiko Saito updated HIVE-13812: ---------------------------------- Description: Create a textfile table with a float column and insert some values: {noformat} 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> create table test(f float); No rows affected (0.237 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> insert into table test values(-35664.76171875),(29497.349609375); INFO : Session is already open INFO : Dag name: insert into table tes...5),(29497.349609375)(Stage-1) INFO : INFO : Status: Running (Executing on YARN cluster with App id application_1463771904371_0006) INFO : Map 1: 0/1 INFO : Map 1: 0/1 INFO : Map 1: 0/1 INFO : Map 1: 0(+1)/1 INFO : Map 1: 1/1 INFO : Loading data to table default.test from hdfs://os-r6-pxwhrs-hiveserver2-3re-5.openstacklocal:8020/apps/hive/warehouse/test/.hive-staging_hive_2016-05-20_21-06-29_377_6487823927119226603-10/-ext-10000 INFO : Table default.test stats: [numFiles=1, numRows=2, totalSize=19, rawDataSize=17] No rows affected (11.069 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> select * from test; +------------------+--+ | test.f | +------------------+--+ | -35664.76171875 | | 29497.349609375 | +------------------+--+ 2 rows selected (0.137 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> describe test; +-----------+------------+----------+--+ | col_name | data_type | comment | +-----------+------------+----------+--+ | f | float | | +-----------+------------+----------+--+ 1 row selected (0.173 seconds) {noformat} Then change float type to string successfully, but when you select table, some fractional digits are lost: {noformat} 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> alter table test change column f f string; No rows affected (0.214 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> describe test; +-----------+------------+----------+--+ | col_name | data_type | comment | +-----------+------------+----------+--+ | f | string | | +-----------+------------+----------+--+ 1 row selected (0.151 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> select * from test; +------------+--+ | test.f | +------------+--+ | -35664.76 | | 29497.35 | +------------+--+ 2 rows selected (0.141 seconds) {noformat} was: Create a table with a float column and insert some values: {noformat} 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> create table test(f float); No rows affected (0.237 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> insert into table test values(-35664.76171875),(29497.349609375); INFO : Session is already open INFO : Dag name: insert into table tes...5),(29497.349609375)(Stage-1) INFO : INFO : Status: Running (Executing on YARN cluster with App id application_1463771904371_0006) INFO : Map 1: 0/1 INFO : Map 1: 0/1 INFO : Map 1: 0/1 INFO : Map 1: 0(+1)/1 INFO : Map 1: 1/1 INFO : Loading data to table default.test from hdfs://os-r6-pxwhrs-hiveserver2-3re-5.openstacklocal:8020/apps/hive/warehouse/test/.hive-staging_hive_2016-05-20_21-06-29_377_6487823927119226603-10/-ext-10000 INFO : Table default.test stats: [numFiles=1, numRows=2, totalSize=19, rawDataSize=17] No rows affected (11.069 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> select * from test; +------------------+--+ | test.f | +------------------+--+ | -35664.76171875 | | 29497.349609375 | +------------------+--+ 2 rows selected (0.137 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> describe test; +-----------+------------+----------+--+ | col_name | data_type | comment | +-----------+------------+----------+--+ | f | float | | +-----------+------------+----------+--+ 1 row selected (0.173 seconds) {noformat} Then change float type to string successfully, but when you select table, some fractional digits are lost: {noformat} 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> alter table test change column f f string; No rows affected (0.214 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> describe test; +-----------+------------+----------+--+ | col_name | data_type | comment | +-----------+------------+----------+--+ | f | string | | +-----------+------------+----------+--+ 1 row selected (0.151 seconds) 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> select * from test; +------------+--+ | test.f | +------------+--+ | -35664.76 | | 29497.35 | +------------+--+ 2 rows selected (0.141 seconds) {noformat} > Change column from float to string group type will drop some factional digits > ----------------------------------------------------------------------------- > > Key: HIVE-13812 > URL: https://issues.apache.org/jira/browse/HIVE-13812 > Project: Hive > Issue Type: Bug > Affects Versions: 1.2.1 > Reporter: Takahiko Saito > > Create a textfile table with a float column and insert some values: > {noformat} > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> create table test(f float); > No rows affected (0.237 seconds) > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> insert into table test > values(-35664.76171875),(29497.349609375); > INFO : Session is already open > INFO : Dag name: insert into table tes...5),(29497.349609375)(Stage-1) > INFO : > INFO : Status: Running (Executing on YARN cluster with App id > application_1463771904371_0006) > INFO : Map 1: 0/1 > INFO : Map 1: 0/1 > INFO : Map 1: 0/1 > INFO : Map 1: 0(+1)/1 > INFO : Map 1: 1/1 > INFO : Loading data to table default.test from > hdfs://os-r6-pxwhrs-hiveserver2-3re-5.openstacklocal:8020/apps/hive/warehouse/test/.hive-staging_hive_2016-05-20_21-06-29_377_6487823927119226603-10/-ext-10000 > INFO : Table default.test stats: [numFiles=1, numRows=2, totalSize=19, > rawDataSize=17] > No rows affected (11.069 seconds) > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> select * from test; > +------------------+--+ > | test.f | > +------------------+--+ > | -35664.76171875 | > | 29497.349609375 | > +------------------+--+ > 2 rows selected (0.137 seconds) > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> describe test; > +-----------+------------+----------+--+ > | col_name | data_type | comment | > +-----------+------------+----------+--+ > | f | float | | > +-----------+------------+----------+--+ > 1 row selected (0.173 seconds) > {noformat} > Then change float type to string successfully, but when you select table, > some fractional digits are lost: > {noformat} > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> alter table test change column > f f string; > No rows affected (0.214 seconds) > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> describe test; > +-----------+------------+----------+--+ > | col_name | data_type | comment | > +-----------+------------+----------+--+ > | f | string | | > +-----------+------------+----------+--+ > 1 row selected (0.151 seconds) > 0: jdbc:hive2://os-r6-pxwhrs-hiveserver2-3re-> select * from test; > +------------+--+ > | test.f | > +------------+--+ > | -35664.76 | > | 29497.35 | > +------------+--+ > 2 rows selected (0.141 seconds) > {noformat} -- This message was sent by Atlassian JIRA (v6.3.4#6332)