Polish codebase: fix grammar, typos, and code quality issues

- Fix grammar in README.md: "incomplete list" → "an incomplete list"
- Improve README.md formatting for better readability
- Fix shell script formatting in generate.sh (add missing space)
- Update PostgreSQL terminology: "master" → "primary" in all SQL files
- Fix typos in SQL comments: "inspect" → "inspects", "Vaccuum" → "Vacuum"
- Remove duplicate random_page_cost entry in t1_tuning.sql
- Remove redundant CTE in i2_redundant_indexes.sql
- Regenerate start.psql file with updated changes

Author: claude

README.md

@@ -14,7 +14,7 @@ Questions? Ideas? Contact me: nik@postgres.ai, Nikolay Samokhvalov.
 
 ## Credits
 
-**postgres_dba** is based on useful queries created and improved by many developers. Here is incomplete list of them:
+**postgres_dba** is based on useful queries created and improved by many developers. Here is an incomplete list of them:
  * Jehan-Guillaume (ioguix) de Rorthais https://github.com/ioguix/pgsql-bloat-estimation
  * Alexey Lesovsky, Alexey Ermakov, Maxim Boguk, Ilya Kosmodemiansky et al. https://github.com/dataegret/pg-utils
  * Josh Berkus, Quinn Weaver et al. from PostgreSQL Experts, Inc. https://github.com/pgexperts/pgx_scripts
@@ -104,9 +104,7 @@ If you are running psql and Postgres server on the same machine, just launch psq
 psql -U <username> <dbname>
 ```
 
-And type `:dba <Enter>` in psql. (Or `\i /path/to/postgres_dba/start.psql` if you haven't added shortcut to your `~/.psqlrc` file).
-
-– it will open interactive menu.
+And type `:dba <Enter>` in psql. (Or `\i /path/to/postgres_dba/start.psql` if you haven't added shortcut to your `~/.psqlrc` file). This will open an interactive menu.
 
 ### Connect to Remote Postgres Server
 What to do if you need to connect to a remote Postgres server? Usually, Postgres is behind a firewall and/or doesn't listen to a public network interface. So you need to be able to connect to the server using SSH. If you can do it, then just create SSH tunnel (assuming that Postgres listens to default port 5432 on that server:

init/generate.sh

@@ -84,5 +84,5 @@ echo "  \\ir ./$OUT" >> "$OUT"
 echo "\\endif" >> "$OUT"
 
 echo "Done."
-cd ->/dev/null
+cd - >/dev/null
 exit 0

sql/0_node.sql

@@ -30,7 +30,7 @@ select
       end)::int)::text || ' second')::interval)::text
     || '; paused: ' || :postgres_dba_is_wal_replay_paused()::text || ')'
   else
-    'Master'
+    'Primary'
   end as value
 union all
 (

sql/b1_table_estimation.sql

@@ -3,7 +3,7 @@
 --This SQL is derived from https://github.com/ioguix/pgsql-bloat-estimation/blob/master/table/table_bloat.sql
 
 /*
-* WARNING: executed with a non-superuser role, the query inspect only tables you are granted to read.
+* WARNING: executed with a non-superuser role, the query inspects only tables you are granted to read.
 * This query is compatible with PostgreSQL 9.0 and more
 */
 
@@ -85,10 +85,10 @@ select
       then '~' || pg_size_pretty((real_size - bloat_size)::numeric)
       else null
    end as "Live",
-  greatest(last_autovacuum, last_vacuum)::timestamp(0)::text 
+  greatest(last_autovacuum, last_vacuum)::timestamp(0)::text
     || case greatest(last_autovacuum, last_vacuum)
       when last_autovacuum then ' (auto)'
-    else '' end as "Last Vaccuum",
+    else '' end as "Last Vacuum",
   (
     select
       coalesce(substring(array_to_string(reloptions, ' ') from 'fillfactor=([0-9]+)')::smallint, 100)

sql/i2_redundant_indexes.sql

@@ -7,7 +7,7 @@
 -- -- so feel free to use it in your clouds (Heroku, AWS RDS, etc)
 
 -- (Keep in mind, that on replicas, the whole picture of index usage
--- is usually very different from master).
+-- is usually very different from the primary).
 
 with fk_indexes as (
   select
@@ -116,12 +116,6 @@ redundant_indexes_tmp_num as (
     *
   from redundant_indexes_tmp_cut
   order by index_size_bytes desc
-), redundant_indexes_grouped as (
-  select
-    distinct(num),
-    *
-  from redundant_indexes_tmp_cut
-  order by index_size_bytes desc
 )
 select
   schema_name,

sql/i4_invalid_indexes.sql

@@ -7,7 +7,7 @@
 -- -- so feel free to use it in your clouds (Heroku, AWS RDS, etc)
 
 -- (Keep in mind, that on replicas, the whole picture of index usage
--- is usually very different from master).
+-- is usually very different from the primary).
 
 select 
     coalesce(nullif(pn.nspname, 'public') || '.', '') || pct.relname as "relation_name",

sql/i5_indexes_migration.sql

@@ -21,9 +21,9 @@
 
 -- It also doesn't do anything except reading system catalogs and
 -- printing NOTICEs, so you can easily run it on your
---  production *master* database.
+--  production *primary* database.
 -- (Keep in mind, that on replicas, the whole picture of index usage
--- is usually very different from master).
+-- is usually very different from the primary).
 
 -- TODO: take into account type of index and opclass
 -- TODO: schemas

sql/t1_tuning.sql

@@ -110,7 +110,6 @@ where
     'autovacuum_vacuum_scale_factor',
     'autovacuum_work_mem',
     'autovacuum_naptime',
-    'random_page_cost',
     'seq_page_cost'
   )
 order by category, name;