Question 90095 in PostgreSQL Question posted in
The official documentation can be found here.

Apache AGE- How to read a CSV File – Postgresql

I am using apache age and I have a CSV file with a bunch of data in it. I want to populate my graph using the information in the csv file, so can anyone help me with this, and also tell me if I have to preprocess my CSV file so that it is readable by the function which is going to be called by apache age.

Tags:

4

Answers


  1. 0

    Yes, you can load data from CSV files into Postrgres using Apache AGE. The docs detail the steps necessary here: https://age.apache.org/age-manual/master/intro/agload.html

    It is likely that you will need to preprocess your files so that the columns and headings are in the correct format.

    Login or Signup to reply.
  2. 0

    Function load_labels_from_file is used to load vertices from the CSV files. Sample format is showing below:

    load_labels_from_file('<graph name>', '<label name>','<file path>')

    As well as if we want to exclude the id field, then we need to add fourth parameter as false which such as:
    *** Use this when there is no id field in the file***

    load_labels_from_file('<graph name>', '<label name>','<file path>',false)

    Again, Function load_edges_from_file can be used to load properties from the CSV file. Please see the file structure in the following.

    Note: make sure that ids in the edge file are identical to ones that are in vertices files.

    load_edges_from_file('<graph name>','<label name>','<file path>');

    You can check this tutorial from official page(age).

    Login or Signup to reply.
  3. 0

    You can populate a graph using the information in the CSV file. According to the documentation, there are two steps for the loading of graph:

    1. loading of vertices and
    2. loading of edges

    ‘load_labels_from_file’ is used to load vertices from the CSV files and ‘load_edges_from_file’ can be used to load properties from the CSV files.

    You can find detailed information about it in this documentation: https://age.apache.org/age-manual/master/intro/agload.html

    Login or Signup to reply.
  4. 0

    In Apache AGE,

    A CSV file containing nodes’ data should be formatted as following:

    id:

    It should be the first column of the file and all values should be a positive integer. This is an optional field when id_field_exists is false. However, it should be present when id_field_exists is not set to false.

    Properties:

    All other columns contains the properties for the nodes. Header row shall contain the name of property

    Create Vertex Lable:

    SELECT create_vlabel('GraphName','LabelName');

    Load Data from CSV:

    SELECT load_labels_from_file('GraphName',
                             'LabelName',
                             'Path/to/file.csv');

    Similarly, In Apache AGE a CSV file for edges should be formatted as follows:

    start_id

    node id of the node from where the edge is stated. This id shall be present in nodes.csv file.

    start_vertex_type

    It should contain class/ label of the node.

    end_id

    The end id of the node at which the edge shall be terminated. This id should also be present in nodes.csv file.

    end_vertex_type

    It should contain class/ label of the node.

    properties

    The properties of the edge. The header (1st Row ) shall contain the property name. 2nd Row and onward rows contains data (values).

    Create Edge Label:

    SELECT create_elabel('GraphName','EdgeLabelName');

    Load Edge Data from csv File:

    SELECT load_edges_from_file('GraphName', 'EdgeLabelName',
     'Path/to/file.csv');

    For more details you can also study this Answer: https://stackoverflow.com/a/76022161/20972645

    Login or Signup to reply.
Please signup or login to give your own answer.

Back To Top
Search