From 779ca0701cfabe659be7a71472bbf9259e696069 Mon Sep 17 00:00:00 2001 From: "Vijayakumar Z @ 'Z" Date: Sun, 19 Feb 2023 09:28:38 +0530 Subject: [PATCH] Create README.md Initial Readme --- README.md | 66 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 66 insertions(+) create mode 100644 README.md diff --git a/README.md b/README.md new file mode 100644 index 0000000..3ccf3a1 --- /dev/null +++ b/README.md @@ -0,0 +1,66 @@ +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: + +git clone https://github.com/yourusername/spark-postgres-schema-generator.git +Install the required modules: + +pip install pyspark psycopg2 +Open the generate_spark_schema.py file in your preferred text editor. + +Update the following variables to match your PostgreSQL database connection details: + + +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: + + +python generate_spark_schema.py +The script will print the generated Spark schema to the console. + +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 + + +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. + +License +This project is licensed under the MIT License. See the LICENSE file for details. + + + +