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Improve defintions of indentation and white space

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Simon Holywell 2015-07-07 15:15:46 +01:00
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@ -8,6 +8,11 @@ or fix bugs please open an [issue](#) or [pull request](#) on Git Hub.
## General
### Do
* Use consistent and descriptive identifiers and names
* Make judicious use of white space to make code easer to read
### Avoid the use of
* CamelCase—it is difficult to scan quickly
@ -25,8 +30,8 @@ SELECT first_name
### Reserved words
Always use uppercase for the [reserved keywords](#reserved-keyword-reference) like
`SELECT` and `WHERE`.
Always use uppercase for the [reserved keywords](#reserved-keyword-reference)
like `SELECT` and `WHERE`.
It is best to avoid the abbreviated keywords and use the full length ones where
available (prefer `ABSOLUTE` to `ABS`).
@ -40,10 +45,54 @@ SELECT model_num
WHERE p.release_date > '2014-09-30';
```
### White space
To make the code easier to read it is important that the correct compliment of
spaces is used. Do not crowd code or remove natural language spaces.
Always include spaces (this is not an exhaustive list):
* before and after equals (`=`)
* after commas (`,`)
* surrounding apostrophes (`'`) where not within parentheses or with a trailing
comma or semicolon
Always include newlines/vertical space:
* after semicolons to separate queries for easier reading
* after each keyword definition
* after a comma when separating multiple columns into logical groups
* before `AND` or `OR`
Keeping all the keywords aligned to the righthand side and the values left aligned
creates a uniform gap down the middle of query. It makes it much easier to scan
the query definition over quickly too.
```sql
-- No
SELECT a.release_date,a.title,a.recording_date,a.production_date
FROM albums AS a
WHERE a.title='Charcoal Lane'OR
a.title='The New Danger';
-- Yes
SELECT a.title,
a.release_date, a.recording_date, a.production_date -- grouped dates together
FROM albums AS a
WHERE a.title = 'Charcoal Lane'
OR a.title = 'The New Danger';
```
### Indentation
To ensure that SQL is readable it is important that standards of indentation
are followed.
#### Joins
Joins should be indented
```sql
SELECT r.last_name
FROM riders AS r
@ -72,45 +121,6 @@ SELECT r.last_name,
AND c.confirmed = 'Y');
```
### White space
To make the code easier to read it is important that the correct compliment of
spaces is used. Do not crowd code or remove natural spaces.
Always include spaces (this is not an exhaustive list):
* before and after equals (`=`)
* after commas (`,`)
* surrounding apostrophes (`'`) where not within parentheses or with a trailing
comma or semicolon
Always include newlines/vertical space:
* after semicolons to separate queries for easier reading
* after each keyword definition
* after the comma of each column in the list
* before `AND` or `OR`
Keeping all the keywords aligned to the righthand side and the values left aligned
creates a uniform gap down the middle of query. It makes it much easier to scan
the query definition over quickly too.
```sql
-- No
SELECT a.release_date,a.title
FROM albums AS a
WHERE a.title='Charcoal Lane'OR
a.title='The New Danger';
-- Yes
SELECT a.release_date,
a.title
FROM albums AS a
WHERE a.title = 'Charcoal Lane'
OR a.title = 'The New Danger';
```
## Naming conventions
### General