afeldman1 commented on a change in pull request #1761: URL: https://github.com/apache/hudi/pull/1761#discussion_r447175985
########## File path: docs/_docs/2_2_writing_data.md ########## @@ -176,15 +176,49 @@ In some cases, you may want to migrate your existing table into Hudi beforehand. ## Datasource Writer -The `hudi-spark` module offers the DataSource API to write (and also read) any data frame into a Hudi table. -Following is how we can upsert a dataframe, while specifying the field names that need to be used -for `recordKey => _row_key`, `partitionPath => partition` and `precombineKey => timestamp` +The `hudi-spark` module offers the DataSource API to write (and read) a Spark DataFrame into a Hudi table. There are a number of options available: +**`HoodieWriteConfig`**: + +**TABLE_NAME** (Required)<br> + + +**`DataSourceWriteOptions`**: + +**RECORDKEY_FIELD_OPT_KEY** (Required): Primary key field(s). Nested fields can be specified using the dot notation eg: `a.b.c`. When using multiple columns as primary key use comma separated notation, eg: `"col1,col2,col3,etc"`. Single or multiple columns as primary key specified by `KEYGENERATOR_CLASS_OPT_KEY` property.<br> +Default value: `"uuid"`<br> + +**PARTITIONPATH_FIELD_OPT_KEY** (Required): Columns to be used for partitioning the table. To prevent partitioning, provide empty string as value eg: `""`. Specify partitioning/no partitioning using `KEYGENERATOR_CLASS_OPT_KEY` and if using hive `HIVE_PARTITION_EXTRACTOR_CLASS_OPT_KEY`<br> +Default value: `"partitionpath"`<br> + +**PRECOMBINE_FIELD_OPT_KEY** (Required): When two records have the same key value, the record with the largest value from the field specified will be choosen.<br> +Default value: `"ts"`<br> + +**OPERATION_OPT_KEY**: The [write operations](#write-operations) to use.<br> +Available values:<br> +`UPSERT_OPERATION_OPT_VAL` (default), `BULK_INSERT_OPERATION_OPT_VAL`, `INSERT_OPERATION_OPT_VAL`, `DELETE_OPERATION_OPT_VAL` + +**TABLE_TYPE_OPT_KEY**: The [type of table](/docs/concepts.html#table-types) to write to. Note: After the initial creation of a table, this value must stay consistent when writing to (updating) the table using the Spark `SaveMode.Append` mode.<br> +Available values:<br> +[`COW_TABLE_TYPE_OPT_VAL`](/docs/concepts.html#copy-on-write-table) (default), [`MOR_TABLE_TYPE_OPT_VAL`](/docs/concepts.html#merge-on-read-table) + +**KEYGENERATOR_CLASS_OPT_KEY**: Key generator class, that will extract the key out of incoming record. If single column key use `SimpleKeyGenerator`. For multiple column keys use `ComplexKeyGenerator`. Note: A custom key generator class can be written/provided here as well. Primary key columns should be provided via `RECORDKEY_FIELD_OPT_KEY` option.<br> +Available values:<br> +`classOf[SimpleKeyGenerator].getName` (default), `classOf[NonpartitionedKeyGenerator].getName` (Non-partitioned tables can currently only have a single key column, [HUDI-1053](https://issues.apache.org/jira/browse/HUDI-1053)), `classOf[ComplexKeyGenerator].getName` + + +**HIVE_PARTITION_EXTRACTOR_CLASS_OPT_KEY**: Specify if the table should or should not be partitioned.<br> Review comment: Also adding clarity that this is only necessary when using hive. ---------------------------------------------------------------- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. For queries about this service, please contact Infrastructure at: [email protected]
