The Merge Columns component merges two tables by column. If this component is used, the two tables must have the same number of rows. If one of the two tables has partitions, the partitioned table must connect to the second input port.

You can configure the component by using one of the following methods:
  • Use the Machine Learning Platform for AI console
    After you select the columns to be merged from the left table, the generated result is saved in the specified columns in the right table. Fields Setting
  • Use commands
    PAI -name appendColumns
    -project algo_public
    -DinputTableNames=maple_test_appendcol_basic_input1,maple_test_appendcol_basic_input2
    -DoutputTableName=maple_test_appendcol_setOutCol_output
    -DoutputTableColNames=x0,x1,x2,x3,x4,x5,x6,x7,x8,x9;
    Parameter Required Description Default value
    inputTableNames Yes The names of two input tables. Separate two table names with a comma (,). N/A
    outputTableName Yes The name of the output table. N/A
    selectedColNamesList No The columns that are selected from the input tables.
    • Separate the columns in a table with commas (,).
    • Separate the columns of different tables with semicolons (;).
    Note If you select all columns in the two tables, the parameter value must be enclosed in double quotation marks ("). Otherwise, the semicolon (;) is processed as the terminator. If all columns in a table are selected, all column names can be omitted, but the semicolons (;) must be retained.
    		N/A
    inputPartitionsInfoList No The partitions that are selected from the input tables.
    • Separate the partitions in a table with forward slashes (/).
    • Separate the partitions of different tables with semicolons (;).
    Note If you select all partitions, the parameter value must be enclosed in quotation marks. Otherwise, the semicolon (;) is processed as the terminator. If a table is not partitioned, all partition names can be omitted, but the semicolons (;) must be retained.
    		N/A
    autoRenameCol No Specifies whether to automatically rename the columns in the output table. false
    outputTableColNames No The new names of the columns in the output table. If this parameter is not specified, the column names in the original table are used.
    Notice If the autoRenameCol parameter is set to true, this parameter is negligible.
    		N/A
    lifecycle No The lifecycle of the output table. The value must be a positive integer. N/A
    coreNum No The number of cores. The value must be a positive integer. This parameter must be used together with the memSizePerCore parameter. Valid values: [1,9999]. Determined by the system
    memSizePerCore No The memory size of each core. The value must be a positive integer. Valid values: [1024,64 x 1024]. Unit: MB. Determined by the system

Example

In this example, the following tables are merged:
  • Source Table 1
    Table 1. maple_test_appendcol_basic_input1
    col0:bigint col1:double col2:string col3:Datetime col4:Boolean
    10 0.0 aaaa 2015-10-01 00:00:00 TRUE
    11 1.0 aaaa 2015-10-01 00:00:00 FALSE
    12 2.0 aaaa 2015-10-01 00:00:00 TRUE
    13 3.0 aaaa 2015-10-01 00:00:00 TRUE
    14 4.0 aaaa 2015-10-01 00:00:00 TRUE
  • Source Table 2
    Table 2. maple_test_appendcol_basic_input2
    col10:bigint col11:double col12:string col13:Datetime col14:Boolean
    110 10.0 2aaaa 2015-10-01 00:00:00 TRUE
    111 11.0 2aaaa 2015-10-01 00:00:00 FALSE
    112 12.0 2aaaa 2015-10-01 00:00:00 TRUE
    113 13.0 2aaaa 2015-10-01 00:00:00 TRUE
    114 14.0 2aaaa 2015-10-01 00:00:00 FALSE
Run the following PAI command to merge the columns of the preceding two source tables. 
PAI -name appendColumns
    -project algo_public
    -DinputTableNames=maple_test_appendcol_basic_input1,maple_test_appendcol_basic_input2
    -DoutputTableName=maple_test_appendcol_setOutCol_output
    -DoutputTableColNames=x0,x1,x2,x3,x4,x5,x6,x7,x8,x9;
The following output table is generated:
Table 3. maple_test_appendcol_setOutCol_output
x0 x1 x2 x3 x4 x5 x6 x7 x8 x9
10 0 aaaa 2015-10-01 00:00:00 true 110 10 2aaaa 2015-10-01 00:00:00 true
11 1 aaaa 2015-10-01 00:00:00 false 111 11 2aaaa 2015-10-01 00:00:00 false
12 2 aaaa 2015-10-01 00:00:00 true 112 12 2aaaa 2015-10-01 00:00:00 true
13 3 aaaa 2015-10-01 00:00:00 true 113 13 2aaaa 2015-10-01 00:00:00 true
14 4 aaaa 2015-10-01 00:00:00 true 114 14 2aaaa 2015-10-01 00:00:00 false