Relax a column in a load append job

  import 
  
 ( 
  
 "context" 
  
 "fmt" 
  
 "os" 
  
 "cloud.google.com/go/bigquery" 
 ) 
 // relaxTableImport demonstrates amending the schema of a table to relax columns from 
 // not allowing NULL values to allowing them. 
 func 
  
 relaxTableImport 
 ( 
 projectID 
 , 
  
 datasetID 
 , 
  
 tableID 
 , 
  
 filename 
  
 string 
 ) 
  
 error 
  
 { 
  
 // projectID := "my-project-id" 
  
 // datasetID := "mydataset" 
  
 // tableID := "mytable" 
  
 ctx 
  
 := 
  
 context 
 . 
 Background 
 () 
  
 client 
 , 
  
 err 
  
 := 
  
 bigquery 
 . 
 NewClient 
 ( 
 ctx 
 , 
  
 projectID 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 fmt 
 . 
 Errorf 
 ( 
 "bigquery.NewClient: %w" 
 , 
  
 err 
 ) 
  
 } 
  
 defer 
  
 client 
 . 
 Close 
 () 
  
 sampleSchema 
  
 := 
  
 bigquery 
 . 
  Schema 
 
 { 
  
 { 
 Name 
 : 
  
 "full_name" 
 , 
  
 Type 
 : 
  
 bigquery 
 . 
  StringFieldType 
 
 , 
  
 Required 
 : 
  
 true 
 }, 
  
 { 
 Name 
 : 
  
 "age" 
 , 
  
 Type 
 : 
  
 bigquery 
 . 
  IntegerFieldType 
 
 , 
  
 Required 
 : 
  
 true 
 }, 
  
 } 
  
 meta 
  
 := 
  
& bigquery 
 . 
  TableMetadata 
 
 { 
  
 Schema 
 : 
  
 sampleSchema 
 , 
  
 } 
  
 tableRef 
  
 := 
  
 client 
 . 
 Dataset 
 ( 
 datasetID 
 ). 
 Table 
 ( 
 tableID 
 ) 
  
 if 
  
 err 
  
 := 
  
 tableRef 
 . 
 Create 
 ( 
 ctx 
 , 
  
 meta 
 ); 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 err 
  
 } 
  
 // Now, import data from a local file, but specify relaxation of required 
  
 // fields as a side effect while the data is appended. 
  
 f 
 , 
  
 err 
  
 := 
  
 os 
 . 
 Open 
 ( 
 filename 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 err 
  
 } 
  
 source 
  
 := 
  
 bigquery 
 . 
  NewReaderSource 
 
 ( 
 f 
 ) 
  
 source 
 . 
 AutoDetect 
  
 = 
  
 true 
  
 // Allow BigQuery to determine schema. 
  
 source 
 . 
 SkipLeadingRows 
  
 = 
  
 1 
  
 // CSV has a single header line. 
  
 loader 
  
 := 
  
 client 
 . 
 Dataset 
 ( 
 datasetID 
 ). 
 Table 
 ( 
 tableID 
 ). 
  LoaderFrom 
 
 ( 
 source 
 ) 
  
 loader 
 . 
 SchemaUpdateOptions 
  
 = 
  
 [] 
 string 
 { 
 "ALLOW_FIELD_RELAXATION" 
 } 
  
 job 
 , 
  
 err 
  
 := 
  
 loader 
 . 
 Run 
 ( 
 ctx 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 err 
  
 } 
  
 status 
 , 
  
 err 
  
 := 
  
 job 
 . 
 Wait 
 ( 
 ctx 
 ) 
  
 if 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 err 
  
 } 
  
 if 
  
 err 
  
 := 
  
 status 
 . 
  Err 
 
 (); 
  
 err 
  
 != 
  
 nil 
  
 { 
  
 return 
  
 err 
  
 } 
  
 return 
  
 nil 
 } 
 

  import 
  
 com.google.cloud.bigquery. BigQuery 
 
 ; 
 import 
  
 com.google.cloud.bigquery. BigQueryException 
 
 ; 
 import 
  
 com.google.cloud.bigquery. BigQueryOptions 
 
 ; 
 import 
  
 com.google.cloud.bigquery. CsvOptions 
 
 ; 
 import 
  
 com.google.cloud.bigquery. Field 
 
 ; 
 import 
  
 com.google.cloud.bigquery. Job 
 
 ; 
 import 
  
 com.google.cloud.bigquery. JobInfo 
 
 ; 
 import 
  
 com.google.cloud.bigquery. LoadJobConfiguration 
 
 ; 
 import 
  
 com.google.cloud.bigquery. Schema 
 
 ; 
 import 
  
 com.google.cloud.bigquery. StandardSQLTypeName 
 
 ; 
 import 
  
 com.google.cloud.bigquery. Table 
 
 ; 
 import 
  
 com.google.cloud.bigquery. TableId 
 
 ; 
 import 
  
 com.google.common.collect.ImmutableList 
 ; 
 // Sample to append relax column in a table. 
 public 
  
 class 
 RelaxColumnLoadAppend 
  
 { 
  
 public 
  
 static 
  
 void 
  
 main 
 ( 
 String 
 [] 
  
 args 
 ) 
  
 { 
  
 // TODO(developer): Replace these variables before running the sample. 
  
 String 
  
 datasetName 
  
 = 
  
 "MY_DATASET_NAME" 
 ; 
  
 String 
  
 tableName 
  
 = 
  
 "MY_TABLE_NAME" 
 ; 
  
 String 
  
 sourceUri 
  
 = 
  
 "gs://cloud-samples-data/bigquery/us-states/us-states.csv" 
 ; 
  
 relaxColumnLoadAppend 
 ( 
 datasetName 
 , 
  
 tableName 
 , 
  
 sourceUri 
 ); 
  
 } 
  
 public 
  
 static 
  
 void 
  
 relaxColumnLoadAppend 
 ( 
 String 
  
 datasetName 
 , 
  
 String 
  
 tableName 
 , 
  
 String 
  
 sourceUri 
 ) 
  
 { 
  
 try 
  
 { 
  
 // Initialize client that will be used to send requests. This client only needs to be created 
  
 // once, and can be reused for multiple requests. 
  
  BigQuery 
 
  
 bigquery 
  
 = 
  
  BigQueryOptions 
 
 . 
 getDefaultInstance 
 (). 
 getService 
 (); 
  
 // Retrieve destination table reference 
  
  Table 
 
  
 table 
  
 = 
  
 bigquery 
 . 
  getTable 
 
 ( 
 TableId 
 . 
 of 
 ( 
 datasetName 
 , 
  
 tableName 
 )); 
  
 // column as a 'REQUIRED' field. 
  
  Field 
 
  
 name 
  
 = 
  
  Field 
 
 . 
 newBuilder 
 ( 
 "name" 
 , 
  
  StandardSQLTypeName 
 
 . 
 STRING 
 ). 
 setMode 
 ( 
  Field 
 
 . 
 Mode 
 . 
 REQUIRED 
 ). 
 build 
 (); 
  
  Field 
 
  
 postAbbr 
  
 = 
  
  Field 
 
 . 
 newBuilder 
 ( 
 "post_abbr" 
 , 
  
  StandardSQLTypeName 
 
 . 
 STRING 
 ) 
  
 . 
 setMode 
 ( 
  Field 
 
 . 
 Mode 
 . 
 REQUIRED 
 ) 
  
 . 
 build 
 (); 
  
  Schema 
 
  
 schema 
  
 = 
  
  Schema 
 
 . 
 of 
 ( 
 name 
 , 
  
 postAbbr 
 ); 
  
 // Skip header row in the file. 
  
  CsvOptions 
 
  
 csvOptions 
  
 = 
  
  CsvOptions 
 
 . 
 newBuilder 
 (). 
 setSkipLeadingRows 
 ( 
 1 
 ). 
 build 
 (); 
  
 // Set job options 
  
  LoadJobConfiguration 
 
  
 loadConfig 
  
 = 
  
  LoadJobConfiguration 
 
 . 
 newBuilder 
 ( 
 table 
 . 
 getTableId 
 (), 
  
 sourceUri 
 ) 
  
 . 
 setSchema 
 ( 
 schema 
 ) 
  
 . 
 setFormatOptions 
 ( 
 csvOptions 
 ) 
  
 . 
 setSchemaUpdateOptions 
 ( 
  
 ImmutableList 
 . 
 of 
 ( 
  JobInfo 
 
 . 
 SchemaUpdateOption 
 . 
 ALLOW_FIELD_RELAXATION 
 )) 
  
 . 
 setWriteDisposition 
 ( 
  JobInfo 
 
 . 
 WriteDisposition 
 . 
 WRITE_APPEND 
 ) 
  
 . 
 build 
 (); 
  
 // Create a load job and wait for it to complete. 
  
  Job 
 
  
 job 
  
 = 
  
 bigquery 
 . 
  create 
 
 ( 
 JobInfo 
 . 
 of 
 ( 
 loadConfig 
 )); 
  
 job 
  
 = 
  
 job 
 . 
  waitFor 
 
 (); 
  
 // Check the job's status for errors 
  
 if 
  
 ( 
 job 
 . 
  isDone 
 
 () 
 && 
 job 
 . 
 getStatus 
 (). 
 getError 
 () 
  
 == 
  
 null 
 ) 
  
 { 
  
 System 
 . 
 out 
 . 
 println 
 ( 
 "Relax column append successfully loaded in a table" 
 ); 
  
 } 
  
 else 
  
 { 
  
 System 
 . 
 out 
 . 
 println 
 ( 
  
 "BigQuery was unable to load into the table due to an error:" 
  
 + 
  
 job 
 . 
 getStatus 
 (). 
 getError 
 ()); 
  
 } 
  
 } 
  
 catch 
  
 ( 
  BigQueryException 
 
  
 | 
  
 InterruptedException 
  
 e 
 ) 
  
 { 
  
 System 
 . 
 out 
 . 
 println 
 ( 
 "Column not added during load append \n" 
  
 + 
  
 e 
 . 
 toString 
 ()); 
  
 } 
  
 } 
 } 
 

  // Import the Google Cloud client libraries 
 const 
  
 { 
 BigQuery 
 } 
  
 = 
  
 require 
 ( 
 ' @google-cloud/bigquery 
' 
 ); 
 // Instantiate client 
 const 
  
 bigquery 
  
 = 
  
 new 
  
  BigQuery 
 
 (); 
 async 
  
 function 
  
 relaxColumnLoadAppend 
 () 
  
 { 
  
 // Changes required column to nullable in load append job. 
  
 /** 
 * TODO(developer): Uncomment the following lines before running the sample. 
 */ 
  
 // const fileName = '/path/to/file.csv'; 
  
 // const datasetId = 'my_dataset'; 
  
 // const tableId = 'my_table'; 
  
 // In this example, the existing table contains the 'Name' 
  
 // column as a 'REQUIRED' field. 
  
 const 
  
 schema 
  
 = 
  
 'Age:INTEGER, Weight:FLOAT, IsMagic:BOOLEAN' 
 ; 
  
 // Retrieve destination table reference 
  
 const 
  
 [ 
 table 
 ] 
  
 = 
  
 await 
  
 bigquery 
 . 
 dataset 
 ( 
 datasetId 
 ). 
 table 
 ( 
 tableId 
 ). 
 get 
 (); 
  
 const 
  
 destinationTableRef 
  
 = 
  
 table 
 . 
 metadata 
 . 
 tableReference 
 ; 
  
 // Set load job options 
  
 const 
  
 options 
  
 = 
  
 { 
  
 schema 
 : 
  
 schema 
 , 
  
 schemaUpdateOptions 
 : 
  
 [ 
 'ALLOW_FIELD_RELAXATION' 
 ], 
  
 writeDisposition 
 : 
  
 'WRITE_APPEND' 
 , 
  
 destinationTable 
 : 
  
 destinationTableRef 
 , 
  
 }; 
  
 // Load data from a local file into the table 
  
 const 
  
 [ 
 job 
 ] 
  
 = 
  
 await 
  
 bigquery 
  
 . 
 dataset 
 ( 
 datasetId 
 ) 
  
 . 
 table 
 ( 
 tableId 
 ) 
  
 . 
  load 
 
 ( 
 fileName 
 , 
  
 options 
 ); 
  
 console 
 . 
 log 
 ( 
 `Job 
 ${ 
  job 
 
 . 
 id 
 } 
 completed.` 
 ); 
  
 // Check the job's status for errors 
  
 const 
  
 errors 
  
 = 
  
  job 
 
 . 
 status 
 . 
 errors 
 ; 
  
 if 
  
 ( 
 errors 
 && 
 errors 
 . 
 length 
 > 
 0 
 ) 
  
 { 
  
 throw 
  
 errors 
 ; 
  
 } 
 } 
 

  # from google.cloud import bigquery 
 # client = bigquery.Client() 
 # project = client.project 
 # dataset_ref = bigquery.DatasetReference(project, 'my_dataset') 
 # filepath = 'path/to/your_file.csv' 
 # Retrieves the destination table and checks the number of required fields 
 table_id 
 = 
 "my_table" 
 table_ref 
 = 
 dataset_ref 
 . 
 table 
 ( 
 table_id 
 ) 
 table 
 = 
 client 
 . 
 get_table 
 ( 
 table_ref 
 ) 
 original_required_fields 
 = 
 sum 
 ( 
 field 
 . 
 mode 
 == 
 "REQUIRED" 
 for 
 field 
 in 
 table 
 . 
 schema 
 ) 
 # In this example, the existing table has 3 required fields. 
 print 
 ( 
 " 
 {} 
 fields in the schema are required." 
 . 
 format 
 ( 
 original_required_fields 
 )) 
 # Configures the load job to append the data to a destination table, 
 # allowing field relaxation 
 job_config 
 = 
 bigquery 
 . 
 LoadJobConfig 
 () 
 job_config 
 . 
 write_disposition 
 = 
 bigquery 
 . 
 WriteDisposition 
 . 
 WRITE_APPEND 
 job_config 
 . 
 schema_update_options 
 = 
 [ 
 bigquery 
 . 
 SchemaUpdateOption 
 . 
 ALLOW_FIELD_RELAXATION 
 ] 
 # In this example, the existing table contains three required fields 
 # ('full_name', 'age', and 'favorite_color'), while the data to load 
 # contains only the first two fields. 
 job_config 
 . 
 schema 
 = 
 [ 
 bigquery 
 . 
 SchemaField 
 ( 
 "full_name" 
 , 
 "STRING" 
 , 
 mode 
 = 
 "REQUIRED" 
 ), 
 bigquery 
 . 
 SchemaField 
 ( 
 "age" 
 , 
 "INTEGER" 
 , 
 mode 
 = 
 "REQUIRED" 
 ), 
 ] 
 job_config 
 . 
 source_format 
 = 
 bigquery 
 . 
 SourceFormat 
 . 
 CSV 
 job_config 
 . 
 skip_leading_rows 
 = 
 1 
 with 
 open 
 ( 
 filepath 
 , 
 "rb" 
 ) 
 as 
 source_file 
 : 
 job 
 = 
 client 
 . 
 load_table_from_file 
 ( 
 source_file 
 , 
 table_ref 
 , 
 location 
 = 
 "US" 
 , 
 # Must match the destination dataset location. 
 job_config 
 = 
 job_config 
 , 
 ) 
 # API request 
 job 
 . 
 result 
 () 
 # Waits for table load to complete. 
 print 
 ( 
 "Loaded 
 {} 
 rows into 
 {} 
 : 
 {} 
 ." 
 . 
 format 
 ( 
 job 
 . 
 output_rows 
 , 
 dataset_id 
 , 
 table_ref 
 . 
 table_id 
 ) 
 ) 
 # Checks the updated number of required fields 
 table 
 = 
 client 
 . 
 get_table 
 ( 
 table 
 ) 
 current_required_fields 
 = 
 sum 
 ( 
 field 
 . 
 mode 
 == 
 "REQUIRED" 
 for 
 field 
 in 
 table 
 . 
 schema 
 ) 
 print 
 ( 
 " 
 {} 
 fields in the schema are now required." 
 . 
 format 
 ( 
 current_required_fields 
 ))