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Information schema doc update (#10081) 

* add docs for IS_JOINABLE and IS_BROADCAST to INFORMATION_SCHEMA docs

* fixes

* oops

* revert noise

* missed one

* spellbot
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Clint Wylie 2020-06-29 21:08:13 -07:00 committed by GitHub
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2 changed files with 18 additions and 10 deletions
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25
docs/querying/sql.md
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@ -921,11 +921,12 @@ SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'druid' AND TABLE_
> `APPROX_QUANTILE_DS`. Only standard SQL functions can be used.
#### SCHEMATA table
`INFORMATION_SCHEMA.SCHEMATA` provides a list of all known schemas, which include `druid` for standard [Druid Table datasources](datasource.md#table), `lookup` for [Lookups](datasource.md#lookup), `sys` for the virtual [System metadata tables](#system-schema), and `INFORMATION_SCHEMA` for these virtual tables. Tables are allowed to have the same name across different schemas, so the schema may be included in an SQL statement to distinguish them, e.g. `lookup.table` vs `druid.table`.
|Column|Notes|
|------|-----|
|CATALOG_NAME|Unused|
|SCHEMA_NAME||
|CATALOG_NAME|Always set as `druid`|
|SCHEMA_NAME|`druid`, `lookup`, `sys`, or `INFORMATION_SCHEMA`|
|SCHEMA_OWNER|Unused|
|DEFAULT_CHARACTER_SET_CATALOG|Unused|
|DEFAULT_CHARACTER_SET_SCHEMA|Unused|
@ -933,23 +934,27 @@ SELECT * FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = 'druid' AND TABLE_
|SQL_PATH|Unused|
#### TABLES table
`INFORMATION_SCHEMA.TABLES` provides a list of all known tables and schemas.
|Column|Notes|
|------|-----|
|TABLE_CATALOG|Always set as 'druid'|
|TABLE_SCHEMA||
|TABLE_NAME||
|TABLE_CATALOG|Always set as `druid`|
|TABLE_SCHEMA|The 'schema' which the table falls under, see [SCHEMATA table for details](#schemata-table)|
|TABLE_NAME|Table name. For the `druid` schema, this is the `dataSource`.|
|TABLE_TYPE|"TABLE" or "SYSTEM_TABLE"|
|IS_JOINABLE|If a table is directly joinable if on the right hand side of a `JOIN` statement, without performing a subquery, this value will be set to `YES`, otherwise `NO`. Lookups are always joinable because they are globally distributed among Druid query processing nodes, but Druid datasources are not, and will use a less efficient subquery join.|
|IS_BROADCAST|If a table is 'broadcast' and distributed among all Druid query processing nodes, this value will be set to `YES`, such as lookups and Druid datasources which have a 'broadcast' load rule, else `NO`.|
#### COLUMNS table
`INFORMATION_SCHEMA.COLUMNS` provides a list of all known columns across all tables and schema.
|Column|Notes|
|------|-----|
|TABLE_CATALOG|Always set as 'druid'|
|TABLE_SCHEMA||
|TABLE_NAME||
|COLUMN_NAME||
|ORDINAL_POSITION||
|TABLE_CATALOG|Always set as `druid`|
|TABLE_SCHEMA|The 'schema' which the table column falls under, see [SCHEMATA table for details](#schemata-table)|
|TABLE_NAME|The 'table' which the column belongs to, see [TABLES table for details](#tables-table)|
|COLUMN_NAME|The column name|
|ORDINAL_POSITION|The order in which the column is stored in a table|
|COLUMN_DEFAULT|Unused|
|IS_NULLABLE||
|DATA_TYPE||

3
website/.spelling
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@ -90,6 +90,8 @@ IANA
IETF
IP
IPv4
IS_BROADCAST
IS_JOINABLE
IS0
ISO-8601
ISO8601
@ -264,6 +266,7 @@ inlined
interruptible
jackson-jq
javadoc
joinable
kerberos
keystore
keytab