Why are the psql results not overlapping?

When working with `psql`, the PostgreSQL interactive terminal, you might notice that the results of your queries typically appear in a structured, tabular format and do not overlap. This is because `psql` is designed to present data in a clear and readable manner, and it uses several mechanisms to prevent overlapping output.

Here are the primary reasons why `psql` results do not overlap:

1. Row-Oriented Display:

- `psql` displays query results row by row. Each row is printed on a new line, ensuring that data from different records is distinctly separated. This row-oriented approach is fundamental to preventing overlap.

2. Column Alignment:

- `psql` automatically aligns columns of the results based on the width of the data in each column. It calculates the maximum width required for each column and then formats the output, ensuring that each value is displayed in its correct column without overlapping adjacent columns.

3. Pager Support:

- If the results of a query are longer than the terminal screen, `psql` often utilizes a pager (like `less` or `more`). The pager allows you to scroll through the output instead of having it all displayed at once, which further avoids potential overlapping. You can also specify the pager in `psql` with `\setenv PAGER 'less -S'`. The `-S` option prevents wrapping.

4. Internal Formatting Logic:

- `psql` has built-in logic to handle various data types and format them consistently. For example, numeric data is right-aligned, text data is left-aligned, and timestamps are formatted according to their specific rules. This consistent formatting contributes to the clarity of the output.

5. Handling of Null Values:

- `psql` also displays null values consistently. Usually, they are shown as an empty space or `NULL`, and it ensures these do not interfere with the layout of other cells.

6. `\x` option for expanded display:

- If the result is wide and you still have issues, you can toggle `\x` to switch to expanded display mode, where rows are displayed vertically with attribute names on the left and attribute values on the right. For example: \x
SELECT FROM my_table LIMIT 2;


7. `\pset` command for formatting:

-The `\pset` command lets you configure how the results are displayed, such as by changing the format to `aligned`, `unaligned`, or `html`. For example \pset format aligned
\pset format unaligned

In summary, `psql`'s non-overlapping results are due to its row-oriented display, column alignment, pager support, internal formatting logic, and explicit handling of data types and `NULL` values. These features combined ensure a readable and organized view of your query results. If you have a very complex output that might still appear confusing, the `\x` or the `\pset` command can offer additional formatting options.

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