ROW_NUMBER ( ) OVER ( PARTITION BY BA.ID ORDER BY BA.CREATETIME DESC

)This SQL statement uses the ROW_NUMBER function to assign a unique sequential number to each row within a specific partition of data. The partition is defined by the BA.ID column, and the rows are ordered by the BA.CREATETIME column in descending order.

The result of this statement is a table that includes the original columns of the data, as well as a new column that contains the assigned row numbers. The row numbers start at 1 for the first row in each partition and increase by 1 for each subsequent row.

This statement can be used to rank or group data within a partition, as well as to filter or join data based on the assigned row numbers.

相关问题

fun_window = Window.partitionBy(primary_keys_list). \ orderBy([F.col(field).desc() for field in self.config.deduplication_order_columns.split(',')]) dataframe_ordered = df.withColumn("row_num_order", F.row_number().over(fun_window)) source_data_df_process = dataframe_ordered.filter(F.col("row_num_order") == 1) df = source_data_df_process.drop("row_num_order")转换为sql语句

SELECT *
FROM (
SELECT *,
ROW_NUMBER() OVER (PARTITION BY primary_key1, primary_key2, ..., primary_keyn
ORDER BY field1 DESC, field2 DESC, ..., fieldn DESC) AS row_num_order
FROM table_name
) t
WHERE t.row_num_order = 1;

row_number() over (partition by a.lot_id order by a.claim_time desc

这是一个SQL Server中的窗口函数，用于为每个分区内的行分配一个唯一的数字。在这个例子中，它将为每个lot_id分区内的行分配一个数字，按照claim_time降序排序。因此，最新的claim_time将获得数字1，其余的行将按照claim_time的降序获得递增的数字。以下是一个示例查询：

SELECT lot_id, claim_time, ROW_NUMBER() OVER(PARTITION BY lot_id ORDER BY claim_time DESC) AS row_num
FROM your_table;