http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3c2c8f12/docs/topics/impala_max_io_buffers.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_max_io_buffers.xml b/docs/topics/impala_max_io_buffers.xml index b08c57e..477c833 100644 --- a/docs/topics/impala_max_io_buffers.xml +++ b/docs/topics/impala_max_io_buffers.xml @@ -3,11 +3,14 @@ <concept id="max_io_buffers"> <title>MAX_IO_BUFFERS Query Option</title> + <titlealts audience="PDF"><navtitle>MAX_IO_BUFFERS</navtitle></titlealts> <prolog> <metadata> <data name="Category" value="Impala"/> <data name="Category" value="Impala Query Options"/> <data name="Category" value="Deprecated Features"/> + <data name="Category" value="Developers"/> + <data name="Category" value="Data Analysts"/> </metadata> </prolog>
http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3c2c8f12/docs/topics/impala_max_scan_range_length.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_max_scan_range_length.xml b/docs/topics/impala_max_scan_range_length.xml index a790fc7..0a31317 100644 --- a/docs/topics/impala_max_scan_range_length.xml +++ b/docs/topics/impala_max_scan_range_length.xml @@ -3,10 +3,14 @@ <concept id="max_scan_range_length"> <title>MAX_SCAN_RANGE_LENGTH Query Option</title> + <titlealts audience="PDF"><navtitle>MAX_SCAN_RANGE_LENGTH</navtitle></titlealts> <prolog> <metadata> <data name="Category" value="Impala"/> <data name="Category" value="Impala Query Options"/> + <data name="Category" value="Performance"/> + <data name="Category" value="Developers"/> + <data name="Category" value="Data Analysts"/> </metadata> </prolog> @@ -38,6 +42,12 @@ <b>Type:</b> numeric </p> + <p rev="IMPALA-3799 CDH-43746"> + In CDH 5.9 / Impala 2.7 and higher, the argument value can include unit specifiers, + such as <codeph>100m</codeph> or <codeph>100mb</codeph>. In previous versions, + Impala interpreted such formatted values as 0, leading to query failures. + </p> + <p> <b>Default:</b> 0 </p> http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3c2c8f12/docs/topics/impala_mem_limit.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_mem_limit.xml b/docs/topics/impala_mem_limit.xml index fd12953..8ed6fbe 100644 --- a/docs/topics/impala_mem_limit.xml +++ b/docs/topics/impala_mem_limit.xml @@ -3,12 +3,16 @@ <concept id="mem_limit"> <title>MEM_LIMIT Query Option</title> + <titlealts audience="PDF"><navtitle>MEM_LIMIT</navtitle></titlealts> <prolog> <metadata> <data name="Category" value="Impala"/> <data name="Category" value="Impala Query Options"/> <data name="Category" value="Scalability"/> <data name="Category" value="Memory"/> + <data name="Category" value="Troubleshooting"/> + <data name="Category" value="Developers"/> + <data name="Category" value="Data Analysts"/> </metadata> </prolog> @@ -78,7 +82,7 @@ <p rev="CDH-32135"> Use the output of the <codeph>SUMMARY</codeph> command in <cmdname>impala-shell</cmdname> - to get a report of memory used for each phase of your most heavyweight queries on each node, + to get a report of memory used for each phase of your most heavyweight queries on each node, and then set a <codeph>MEM_LIMIT</codeph> somewhat higher than that. See <xref href="impala_explain_plan.xml#perf_summary"/> for usage information about the <codeph>SUMMARY</codeph> command. @@ -199,7 +203,7 @@ Query: select count(distinct c_name) from customer MEM_LIMIT set to 15mb [localhost:21000] > select count(distinct c_name) from customer; Query: select count(distinct c_name) from customer -ERROR: +ERROR: Memory limit exceeded Query did not have enough memory to get the minimum required buffers in the block manager. </codeblock> http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3c2c8f12/docs/topics/impala_min.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_min.xml b/docs/topics/impala_min.xml index a63fc4c..047b4ef 100644 --- a/docs/topics/impala_min.xml +++ b/docs/topics/impala_min.xml @@ -2,7 +2,7 @@ <concept id="min"> <title>MIN Function</title> - <titlealts><navtitle>MIN</navtitle></titlealts> + <titlealts audience="PDF"><navtitle>MIN</navtitle></titlealts> <prolog> <metadata> <data name="Category" value="Impala"/> @@ -11,6 +11,8 @@ <data name="Category" value="Analytic Functions"/> <data name="Category" value="Aggregate Functions"/> <data name="Category" value="Querying"/> + <data name="Category" value="Developers"/> + <data name="Category" value="Data Analysts"/> </metadata> </prolog> @@ -38,10 +40,14 @@ <p conref="../shared/impala_common.xml#common/return_type_same_except_string"/> + <p conref="../shared/impala_common.xml#common/usage_notes_blurb"/> + + <p conref="../shared/impala_common.xml#common/partition_key_optimization"/> + <p conref="../shared/impala_common.xml#common/complex_types_blurb"/> <p conref="../shared/impala_common.xml#common/complex_types_aggregation_explanation"/> - + <p conref="../shared/impala_common.xml#common/complex_types_aggregation_example"/> <p conref="../shared/impala_common.xml#common/example_blurb"/> @@ -155,7 +161,7 @@ analytic context, the lower bound must be <codeph>UNBOUNDED PRECEDING</codeph>. ( <b>order by property, x desc</b> <b>rows between unbounded preceding and 1 following</b> - ) as 'local minimum' + ) as 'local minimum' from int_t where property in ('prime','square'); +---+----------+---------------+ | x | property | local minimum | http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3c2c8f12/docs/topics/impala_misc_functions.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_misc_functions.xml b/docs/topics/impala_misc_functions.xml index bb9f062..196f3c2 100644 --- a/docs/topics/impala_misc_functions.xml +++ b/docs/topics/impala_misc_functions.xml @@ -3,7 +3,7 @@ <concept id="misc_functions"> <title>Impala Miscellaneous Functions</title> - <titlealts><navtitle>Miscellaneous Functions</navtitle></titlealts> + <titlealts audience="PDF"><navtitle>Miscellaneous Functions</navtitle></titlealts> <prolog> <metadata> <data name="Category" value="Impala"/> @@ -111,7 +111,7 @@ <indexterm audience="Cloudera">user() function</indexterm> <b>Purpose:</b> Returns the username of the Linux user who is connected to the <cmdname>impalad</cmdname> daemon. Typically called a single time, in a query without any <codeph>FROM</codeph> clause, to - understand how authorization settings apply in a security context; once you know the logged-in user name, + understand how authorization settings apply in a security context; once you know the logged-in username, you can check which groups that user belongs to, and from the list of groups you can check which roles are available to those groups through the authorization policy file. <p conref="../shared/impala_common.xml#common/user_kerberized"/> @@ -125,6 +125,54 @@ </dlentry> + <dlentry rev="2.5.0 IMPALA-1477" id="uuid"> + + <dt> + <codeph>uuid()</codeph> + </dt> + + <dd> + <indexterm audience="Cloudera">uuid() function</indexterm> + <b>Purpose:</b> Returns a <xref href="https://en.wikipedia.org/wiki/Universally_unique_identifier"; scope="external" format="html">universal unique identifier</xref>, a 128-bit value encoded as a string with groups of hexadecimal digits separated by dashes. + <p> + <b>Return type:</b> <codeph>string</codeph> + </p> + <p conref="../shared/impala_common.xml#common/added_in_250"/> + <p conref="../shared/impala_common.xml#common/usage_notes_blurb"/> + <p> + Ascending numeric sequences of type <codeph>BIGINT</codeph> are often used + as identifiers within a table, and as join keys across multiple tables. + The <codeph>uuid()</codeph> value is a convenient alternative that does not + require storing or querying the highest sequence number. For example, you + can use it to quickly construct new unique identifiers during a data import job, + or to combine data from different tables without the likelihood of ID collisions. + </p> + <p conref="../shared/impala_common.xml#common/example_blurb"/> +<codeblock> +-- Each call to uuid() produces a new arbitrary value. +select uuid(); ++--------------------------------------+ +| uuid() | ++--------------------------------------+ +| c7013e25-1455-457f-bf74-a2046e58caea | ++--------------------------------------+ + +-- If you get a UUID for each row of a result set, you can use it as a +-- unique identifier within a table, or even a unique ID across tables. +select uuid() from four_row_table; ++--------------------------------------+ +| uuid() | ++--------------------------------------+ +| 51d3c540-85e5-4cb9-9110-604e53999e2e | +| 0bb40071-92f6-4a59-a6a4-60d46e9703e2 | +| 5e9d7c36-9842-4a96-862d-c13cd0457c02 | +| cae29095-0cc0-4053-a5ea-7fcd3c780861 | ++--------------------------------------+ +</codeblock> + </dd> + + </dlentry> + <dlentry id="version"> <dt> http://git-wip-us.apache.org/repos/asf/incubator-impala/blob/3c2c8f12/docs/topics/impala_ndv.xml ---------------------------------------------------------------------- diff --git a/docs/topics/impala_ndv.xml b/docs/topics/impala_ndv.xml index a1e5527..fcdae77 100644 --- a/docs/topics/impala_ndv.xml +++ b/docs/topics/impala_ndv.xml @@ -3,7 +3,7 @@ <concept rev="1.2.1" id="ndv"> <title>NDV Function</title> - <titlealts><navtitle>NDV</navtitle></titlealts> + <titlealts audience="PDF"><navtitle>NDV</navtitle></titlealts> <prolog> <metadata> <data name="Category" value="Impala"/> @@ -11,6 +11,8 @@ <data name="Category" value="Impala Functions"/> <data name="Category" value="Aggregate Functions"/> <data name="Category" value="Querying"/> + <data name="Category" value="Developers"/> + <data name="Category" value="Data Analysts"/> </metadata> </prolog> @@ -43,12 +45,12 @@ <p conref="../shared/impala_common.xml#common/former_odd_return_type_string"/> -<!-- <p conref="/Content/impala_common_xi44078.xml#common/restrictions_sliding_window"/> --> +<!-- <p conref="../shared/impala_common.xml#common/restrictions_sliding_window"/> --> <p conref="../shared/impala_common.xml#common/complex_types_blurb"/> <p conref="../shared/impala_common.xml#common/complex_types_aggregation_explanation"/> - + <p conref="../shared/impala_common.xml#common/complex_types_aggregation_example"/> <p conref="../shared/impala_common.xml#common/restrictions_blurb"/>
