How to Print SQL Queries in SQLAlchemy with Actual Values?

Retrieving SQL Queries in SQLAlchemy with Actual Values

When using SQLAlchemy, it can be useful to print the actual SQL queries being executed, including the specific values being used, rather than the abstract bind parameters.

Here's how to achieve this in SQLAlchemy:

<code class="python">print(str(statement))</code>

This simple approach works for both ORM Query objects and select() or other statement types. If you want to obtain the query as compiled to a specific dialect or engine, you can pass in the appropriate arguments to compile():

<code class="python">print(statement.compile(someengine))
print(statement.compile(dialect=postgresql.dialect()))</code>

When using ORM Query objects, first access the .statement accessor to get at the compile() method:

<code class="python">statement = query.statement
print(statement.compile(someengine))</code>

In cases where you need to inline bound parameters into the final string, SQLAlchemy has limited support for this. You can use the 'literal_binds' flag when calling compile():

<code class="python">print(s.compile(compile_kwargs={"literal_binds": True}))</code>

However, this only works for simple types like integers and strings. For custom types, you'll need to use a TypeDecorator with a TypeDecorator.process_literal_param method to provide custom formatting:

<code class="python">print(
    tab.select().where(tab.c.x > 5).compile(
        compile_kwargs={"literal_binds": True})
)</code>

This approach allows for inline rendering of custom types in the resulting SQL query string.

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