WitrynaSHOW TABLE STATS provides some general information about the table, such as the number of files, overall size of the data, whether some or all of the data is in … WitrynaThe Impala query planner can make use of statistics about individual columns when that metadata is available in the metastore database. This technique is most valuable …

UPDATE Statement (Impala 2.8 or higher only) - The Apache …

WitrynaExamples of Using Table and Column Statistics with Impala. The following examples walk through a sequence of SHOW TABLE STATS, SHOW COLUMN STATS, … Witryna4 lip 2014 · 4 Answers. Use show create table. Read the hive manual for more detail. It is DESCRIBE [EXTENDED FORMATTED] also. show create table doesn't give enough information sometimes, but DESCRIBE always does; For a view, DESCRIBE EXTENDED or FORMATTED can be used to retrieve the view's definition. irs audit department phone number

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WitrynaThe SHOW CURRENT ROLE statement displays roles assigned to the current user. This syntax is available in Impala 2.0 and later only, when you are using the Sentry … WitrynaThe DESCRIBE statement displays metadata about a table, such as the column names and their data types. In Impala 2.3 and higher, you can specify the name of a complex type column, which takes the form of a dotted path. The path might include multiple components in the case of a nested type definition. In Impala 2.5 and higher, the … Witryna因为Impala目前在查询规划期间不使用空计数，所以Impala 1.4.0及更高版本通过跳过这个空计数来加速COMPUTE STATS语句。 内部细节: 在后台，COMPUTE STATS语句执行两条语句:一条通过count(*)函数计算表中每个分区(或者未分区的整个表)的行数，另一条通过NDV()函数计算每列 ... irs audit process steps