Configure an auto-increment primary key column

Prerequisites

The OTSClient instance is initialized. For more information, see Initialization.

Usage notes

1. When you create a table, you cannot set the partition key to an auto-increment primary key column.

   An auto-increment primary key column can only be an integer column. The generated value for an auto-increment primary key column is a 64-bit signed long integer.

2. When you write data to a table, you do not need to specify a specific value for the auto-increment column. Instead, you need only to set the value of the auto-increment column to the auto-increment primary key column.

   If you want to obtain the value of the auto-increment column after data is written to the table, you can set ReturnType to RT_PK.

   When you query data, you must specify the values of all primary key columns. To obtain a complete primary key value, you can set ReturnType to RT_PK in PutRow, UpdateRow, or BatchWriteRow.

Examples

When you use auto-increment primary key columns, you can call the CreateTable, PutRow, UpdateRow, or BatchWriteRow operation.

1. Create a table

   To create an auto-increment primary key column when you create a table, you must set the attribute of the primary key column to AUTO_INCREMENT.

   import (
       "fmt"
       "github.com/aliyun/aliyun-tablestore-go-sdk/tablestore"
   )
   
   func CreateTableKeyAutoIncrementSample(client *tablestore.TableStoreClient) {
       createtableRequest := new(tablestore.CreateTableRequest)
       // Create a table that contains three primary key columns: pk1 of the STRING type, pk2 of the INTEGER type, and pk3 of the BINARY type. pk2 is the auto-increment primary key column.
       tableMeta := new(tablestore.TableMeta)
       tableMeta.TableName = "incrementsampletable"
       tableMeta.AddPrimaryKeyColumn("pk1", tablestore.PrimaryKeyType_STRING)
       tableMeta.AddPrimaryKeyColumnOption("pk2", tablestore.PrimaryKeyType_INTEGER, tablestore.AUTO_INCREMENT)
       tableMeta.AddPrimaryKeyColumn("pk3", tablestore.PrimaryKeyType_BINARY)
       tableOption := new(tablestore.TableOption)
       tableOption.TimeToAlive = -1
       tableOption.MaxVersion = 3
       reservedThroughput := new(tablestore.ReservedThroughput)
       reservedThroughput.Readcap = 0
       reservedThroughput.Writecap = 0
       createtableRequest.TableMeta = tableMeta
       createtableRequest.TableOption = tableOption
       createtableRequest.ReservedThroughput = reservedThroughput
   
       client.CreateTable(createtableRequest)
   }

2. Write data

   When you write data to a table, you do not need to specify a specific value for the auto-increment column. Instead, you need only to set the value of the auto-increment column to the auto-increment primary key column.

   import (
       "fmt"
       "github.com/aliyun/aliyun-tablestore-go-sdk/tablestore"
   )
   
   func PutRowWithKeyAutoIncrementSample(client *tablestore.TableStoreClient) {
       fmt.Println("begin to put row")
       putRowRequest := new(tablestore.PutRowRequest)
       putRowChange := new(tablestore.PutRowChange)
       putRowChange.TableName = "incrementsampletable"
       // Specify primary key columns, which must be added in the order specified when the table is created. Set pk2 to the auto-increment primary key column.
       putPk := new(tablestore.PrimaryKey)
       putPk.AddPrimaryKeyColumn("pk1", "pk1value1")
       putPk.AddPrimaryKeyColumnWithAutoIncrement("pk2")
       putPk.AddPrimaryKeyColumn("pk3", []byte("pk3"))
       putRowChange.PrimaryKey = putPk
       putRowChange.AddColumn("col1", "col1data1")
       putRowChange.AddColumn("col2", int64(100))
       putRowChange.SetCondition(tablestore.RowExistenceExpectation_IGNORE)
       putRowRequest.PutRowChange = putRowChange
       _, err := client.PutRow(putRowRequest)
   
       if err != nil {
           fmt.Println("put row failed with error:", err)
       } else {
           fmt.Println("put row finished")
       }
   }