QueryRecord 2.0.0

Bundle
org.apache.nifi | nifi-standard-nar
Description
Evaluates one or more SQL queries against the contents of a FlowFile. The result of the SQL query then becomes the content of the output FlowFile. This can be used, for example, for field-specific filtering, transformation, and row-level filtering. Columns can be renamed, simple calculations and aggregations performed, etc. The Processor is configured with a Record Reader Controller Service and a Record Writer service so as to allow flexibility in incoming and outgoing data formats. The Processor must be configured with at least one user-defined property. The name of the Property is the Relationship to route data to, and the value of the Property is a SQL SELECT statement that is used to specify how input data should be transformed/filtered. The SQL statement must be valid ANSI SQL and is powered by Apache Calcite. If the transformation fails, the original FlowFile is routed to the 'failure' relationship. Otherwise, the data selected will be routed to the associated relationship. If the Record Writer chooses to inherit the schema from the Record, it is important to note that the schema that is inherited will be from the ResultSet, rather than the input Record. This allows a single instance of the QueryRecord processor to have multiple queries, each of which returns a different set of columns and aggregations. As a result, though, the schema that is derived will have no schema name, so it is important that the configured Record Writer not attempt to write the Schema Name as an attribute if inheriting the Schema from the Record. See the Processor Usage documentation for more information.
Tags
aggregate, avro, calcite, csv, etl, filter, json, logs, modify, query, record, route, select, sql, text, transform, update
Input Requirement
REQUIRED
Supports Sensitive Dynamic Properties
false
Properties
Dynamic Properties
Relationships
Name Description
failure If a FlowFile fails processing for any reason (for example, the SQL statement contains columns not present in input data), the original FlowFile it will be routed to this relationship
original The original FlowFile is routed to this relationship
Writes Attributes
Name Description
mime.type Sets the mime.type attribute to the MIME Type specified by the Record Writer
record.count The number of records selected by the query
QueryRecord.Route The relation to which the FlowFile was routed
Use Cases
  • Filter out records based on the values of the records' fields
    Description
    Filter out records based on the values of the records' fields
    Keywords
    filter out, remove, drop, strip out, record field, sql
    Configuration
    "Record Reader" should be set to a Record Reader that is appropriate for your data.
"Record Writer" should be set to a Record Writer that writes out data in the desired format.

One additional property should be added.
The name of the property should be a short description of the data to keep.
Its value is a SQL statement that selects all columns from a table named `FLOW_FILE` for relevant rows.
The WHERE clause selects the data to keep. I.e., it is the exact opposite of what we want to remove.
It is recommended to always quote column names using double-quotes in order to avoid conflicts with SQL keywords.
For example, to remove records where either the name is George OR the age is less than 18, we would add a   property named "adults not george" with a value that selects records where the name is not George AND the age is greater than or equal to 18.   So the value would be `SELECT * FROM FLOWFILE WHERE "name" <> 'George' AND "age" >= 18`

Adding this property now gives us a new Relationship whose name is the same as the property name. So, the "adults not george" Relationship should be connected to the next Processor in our flow.
  • Keep only specific records
    Description
    Keep only specific records
    Keywords
    keep, filter, retain, select, include, record, sql
    Configuration
    "Record Reader" should be set to a Record Reader that is appropriate for your data.
"Record Writer" should be set to a Record Writer that writes out data in the desired format.

One additional property should be added.
The name of the property should be a short description of the data to keep.
Its value is a SQL statement that selects all columns from a table named `FLOW_FILE` for relevant rows.
The WHERE clause selects the data to keep.
It is recommended to always quote column names using double-quotes in order to avoid conflicts with SQL keywords.
For example, to keep only records where the person is an adult (aged 18 or older), add a property named "adults"   with a value that is a SQL statement that selects records where the age is at least 18.   So the value would be `SELECT * FROM FLOWFILE WHERE "age" >= 18`

Adding this property now gives us a new Relationship whose name is the same as the property name. So, the "adults" Relationship should be connected to the next Processor in our flow.
  • Keep only specific fields in a a Record, where the names of the fields to keep are known
    Description
    Keep only specific fields in a a Record, where the names of the fields to keep are known
    Keywords
    keep, filter, retain, select, include, record, fields, sql
    Configuration
    "Record Reader" should be set to a Record Reader that is appropriate for your data.
"Record Writer" should be set to a Record Writer that writes out data in the desired format.

One additional property should be added.
The name of the property should be a short description of the data to keep, such as `relevant fields`.
Its value is a SQL statement that selects the desired columns from a table named `FLOW_FILE` for relevant rows.
There is no WHERE clause.
It is recommended to always quote column names using double-quotes in order to avoid conflicts with SQL keywords.
For example, to keep only the `name`, `age`, and `address` fields, add a property named `relevant fields`   with a value of `SELECT "name", "age", "address" FROM FLOWFILE`

Adding this property now gives us a new Relationship whose name is the same as the property name. So, the `relevant fields` Relationship should be connected to the next Processor in our flow.
  • Route record-oriented data for processing based on its contents
    Description
    Route record-oriented data for processing based on its contents
    Keywords
    record, route, conditional processing, field
    Configuration
    "Record Reader" should be set to a Record Reader that is appropriate for your data.
"Record Writer" should be set to a Record Writer that writes out data in the desired format.

For each route that you want to create, add a new property.
The name of the property should be a short description of the data that should be selected for the route.
Its value is a SQL statement that selects all columns from a table named `FLOW_FILE`. The WHERE clause selects the data that should be included in the route.
It is recommended to always quote column names using double-quotes in order to avoid conflicts with SQL keywords.

A new outbound relationship is created for each property that is added. The name of the relationship is the same as the property name.

For example, to route data based on whether or not it is a large transaction, we would add two properties:
`small transaction` would have a value such as `SELECT * FROM FLOWFILE WHERE transactionTotal < 100`
`large transaction` would have a value of `SELECT * FROM FLOWFILE WHERE transactionTotal >= 100`