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README.md

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+# dbt-no-select-star
+![Ah! Ah! Ah!](etc/ah-ah-ah.gif)
+
+This [dbt](https://github.com/dbt-labs/dbt) package contains a macro that will throw an error if you attempt to use `select *` in your model. This macro effectively forces you to be explicit about the columns you want to select.
+
+## Installation
+Adding this package to your project will enable the macro. To install, add the following to your `packages.yml` file:
+
+```yml
+packages:
+  - git: "https://github.com/patricktrainer/dbt-no-select-star.git"
+    revision: 0.1.0
+```
+
+## Usage
+To use the macro, simply add the following at the end of your model:
+
+```sql
+{{ no_select_star() }}
+```
+
+For example:
+
+```sql
+select 
+  my_column,
+  my_other_column,
+  {{ no_select_star() }}
+from {{ ref(my_table) }}
+```
+
+This will throw an error if you attempt to use `select *` in your model.
+
+The error message will look like this:
+
+```bash
+'DONT SELECT * FROM THIS TABLE!!!1'
+```
+
+To avoid the error, be explicit about the columns you want to select:
+
+```sql
+select 
+  my_column,
+  my_other_column
+from {{ ref(my_table) }}
+```
+
+## How does this work?
+This works by leveraging _computed columns_. Computed columns are a feature that allow you to create a column that is the result of a SQL expression. If you inspect [the macro](macros/no_select_star.sql), you'll notice that it creates a `string` typed column. This column is then cast as a `char()` type with a length of 1 byte. Obviously, the string "DONT SELECT * FROM THIS TABLE!!!1" is longer than 1 byte, so the cast will fail. This will cause the query to fail, and the error message will be displayed.