Question

如何创建和替换现有的BigQuery表？我使用datalab定义BigQuery查询并将结果写入BigQuery表。

我发现这样做最有效的方法是：

%%bq query --name helloWorld
Select * from someTable

其次是

%%bq execute --table schemaName.destination_table --query helloWorld

但是我每次都必须手动删除表

从命令行我可以执行以下操作：

bq query --destination_table [PROJECT_ID]:[DATASET].[TABLE] --replace '[QUERY]'

python / Datalab中是否有类似的功能？

Answer 1

使用--mode或-m参数。例如：

%%bq execute --table schemaName.destination_table --query helloWorld --mode overwrite

运行%%bq execute --help：

查看更多选项

usage: %bq execute [-h] [-nc] [-b BILLING] [-m {create,append,overwrite}] [-l]
                   -q QUERY [-t TABLE] [--to-dataframe]
                   [--dataframe-start-row DATAFRAME_START_ROW]
                   [--dataframe-max-rows DATAFRAME_MAX_ROWS] [-v]

Execute a BigQuery SQL query and optionally send the results to a named table.
The cell can optionally contain arguments for expanding variables in the
query.

optional arguments:
  -h, --help            show this help message and exit
  -nc, --nocache        Don't use previously cached results
  -b BILLING, --billing BILLING
                        BigQuery billing tier
  -m {create,append,overwrite}, --mode {create,append,overwrite}
                        The table creation mode
  -l, --large           Whether to allow large results
  -q QUERY, --query QUERY
                        The name of query to run
  -t TABLE, --table TABLE
                        Target table name
  --to-dataframe        Convert the result into a dataframe
  --dataframe-start-row DATAFRAME_START_ROW
                        Row of the table to start the dataframe export
  --dataframe-max-rows DATAFRAME_MAX_ROWS
                        Upper limit on number of rows to export to the
                        dataframe
  -v, --verbose         Show the expanded SQL that is being executed

创建和替换BigQuery表

1 个答案: