使用GOLANG V2 API在Google BigQuery中进行参数化查询

Question

Im currently unable to use parameterized queries to Google BigQuery using the V2 API in GOLANG. Typically without the paramters the code to process the query would be:

database_query := client.Query(report.Query) database_query.QueryConfig.Dst = table_result job, err := database_query.Run(ctx)

assume that we dont use the named paramters. lets mock 2 parameters and append this to the request as expected from the API(https://github.com/GoogleCloudPlatform/google-cloud-go/blob/master/bigquery/query.go) :

var params [2]string
params[0] = "currency"
params[1] = "price"

ParametersL := make([]bigquery.QueryParameter, 0)
for _,element := range params {
    temp := bigquery.QueryParameter{}
    temp.Value=element
    ParametersL = append(ParametersL,temp)
}

database_query := client.Query(report.Query)
database_query.QueryConfig.Dst = table_result
database_query.QueryConfig.Parameters= ParametersL

provided you manage to squeeze the '?' into the appropriate place into the query you either get a error prompting missing , after FROM or the other ? is not recognized. The same goes for named paramters using @. Am I missing something cruzial or is the paramters not supported for GOLANG API?

Answer 1

You need to set UseStandardSQL as part of QueryConfig, since query parameters are supported only with standard SQL. You will also need to make sure to set the Type attribute of the QueryParameters, which should be "STRING". While positional parameters are supported, of course, I would still suggest using named parameters, since they make refactoring easier if you need to modify the query string at some point.