Spark DDL 模式 JSON 结构

Question

问题

我正在尝试在 pyspark 中定义一个嵌套的 .json 模式，但无法使 ddl_schema 字符串起作用。

通常在 SQL 中这将是 ROW，我在下面尝试了 STRUCT 但无法正确获取数据类型这是错误...

ParseException: 
mismatched input '(' expecting {<EOF>, ',', 'COMMENT', NOT}(line 6, pos 15)

== SQL ==

    driverId INT,
    driverRef STRING,
    number STRING,
    code STRING,
    name STRUCT(forename STRING, surname STRING),
---------------^^^
    dob DATE,
    nationality STRING,
    url STRING

数据样本

            +--------+----------+------+----+--------------------+----------+-----------+--------------------+
            |driverId| driverRef|number|code|                name|       dob|nationality|                 url|
            +--------+----------+------+----+--------------------+----------+-----------+--------------------+
            |       1|  hamilton|    44| HAM|   {Lewis, Hamilton}|1985-01-07|    British|http://en.wikiped...|

代码示例

        mnt = "/mnt/dev/root"
        env = "raw"
        path = "formula1/drivers"
        fileFormat = "json"
        
        inPath = f"{mnt}/{env.upper()}/{path}.{fileFormat}"
        
        
        options = {'header': 'True'}
        
        ddl_schema = """
            driverId INT,
            driverRef STRING,
            number STRING,
            code STRING,
            name STRUCT(forename STRING, surname STRING),
            dob DATE,
            nationality STRING,
            url STRING
        """
        
        drivers_df = (spark
                       .read
                       .options(**options)
                       .schema(ddl_schema)
                       .format(fileFormat)
                       .load(inPath)
                     )

Answer 1

您对 STRUCT 使用了错误的语法。
这是正确的：

name STRUCT<forename:STRING,surname:STRING>

https://spark.apache.org/docs/latest/sql-ref-datatypes.html
（搜索 Complex types 并选择 SQL 选项卡）

Data type	SQL name
BooleanType	BOOLEAN
ByteType	BYTE, TINYINT
ShortType	SHORT, SMALLINT
IntegerType	INT, INTEGER
LongType	LONG, BIGINT
FloatType	FLOAT, REAL
DoubleType	DOUBLE
DateType	DATE
TimestampType	TIMESTAMP
StringType	STRING
BinaryType	BINARY
DecimalType	DECIMAL, DEC, NUMERIC
YearMonthIntervalType	INTERVAL YEAR, INTERVAL YEAR TO MONTH, INTERVAL MONTH
DayTimeIntervalType	INTERVAL DAY, INTERVAL DAY TO HOUR, INTERVAL DAY TO MINUTE, INTERVAL DAY TO SECOND, INTERVAL HOUR, INTERVAL HOUR TO MINUTE, INTERVAL HOUR TO SECOND, INTERVAL MINUTE, INTERVAL MINUTE TO SECOND, INTERVAL SECOND
ArrayType	ARRAY<element_type>
StructType	STRUCT<field1_name: field1_type, field2_name: field2_type, …> Note: ‘:’ is optional.
MapType	MAP<key_type, value_type>

Spark DDL 模式 JSON 结构

Spark DDL Schema JSON Struct

ddl

json

apache-spark

apache-spark-sql

pyspark

问题

数据样本

代码示例