diff --git a/README.md b/README.md index 3ccf3a1..a733636 100644 --- a/README.md +++ b/README.md @@ -1,66 +1,56 @@ -Spark Schema Generator from PostgreSQL Table Schema -This repository contains a Python script that generates a Spark StructType schema from a PostgreSQL table schema. + -Requirements -To use the script, you will need: + -Python 3.x -pyspark module -psycopg2 module -Access to a PostgreSQL database with the schema you want to generate a Spark schema for -Usage -Clone the repository to your local machine: +

PySpark StructType schema generator from PostgreSQL table schema

-git clone https://github.com/yourusername/spark-postgres-schema-generator.git -Install the required modules: +

This Python program generates a PySpark StructType schema from a PostgreSQL table schema. The program connects to a PostgreSQL database, reads the schema of the specified table, and maps the PostgreSQL data types to the corresponding PySpark data types.

-pip install pyspark psycopg2 -Open the generate_spark_schema.py file in your preferred text editor. +

Prerequisites

-Update the following variables to match your PostgreSQL database connection details: + +

Usage

-host = "localhost" -database = "mydb" -user = "myuser" -password = "mypassword" -Update the schema_name variable to match the name of the PostgreSQL schema you want to generate a Spark schema for: +
    +
  1. Clone the repository: git clone https://github.com/username/repo.git
  2. +
  3. Navigate to the directory: cd repo
  4. +
  5. Edit the config.ini file to specify the PostgreSQL database connection parameters and the name of the table to generate the schema from
  6. +
  7. Run the program: python generate_schema.py
  8. +
+

Configuring the program

-python generate_spark_schema.py -The script will print the generated Spark schema to the console. +

The program can be configured by editing the config.ini file. The file contains the following parameters:

-Supported PostgreSQL Data Types -The script supports the following PostgreSQL data types: + -ARRAY -bigint -boolean -bytea -character -character varying -date -double precision -integer -json -name -numeric -oid -smallint -text -timestamp with time zone -timestamp without time zone +

Example output

+

The program generates output similar to the following:

-Notes -The script assumes that any PostgreSQL column with a NOT NULL constraint is required in the Spark schema, and any column without a NOT NULL constraint is nullable in the Spark schema. -The script assumes that any PostgreSQL array column contains string elements. -The script assumes that any PostgreSQL numeric column has a specified precision and scale. If your database uses the default precision and scale for numeric columns, you may need to modify the script to handle this case. -The script assumes that the PostgreSQL schema name you provide has access to the tables you want to generate a Spark schema for. If you need to generate a schema for tables in a different schema, you will need to update the script accordingly. +
StructType(List(StructField(id,IntegerType,true),StructField(name,StringType,true),StructField(age,IntegerType,true)))
-License -This project is licensed under the MIT License. See the LICENSE file for details. +

Contributing

+

Contributions are welcome! Please submit a pull request if you'd like to contribute.

+

License

+

This program is licensed under the MIT license. See the LICENSE.md file for details.

+ + +