Tag: snippets

Am I Inside A Screen Session?

Check

$STY

. If it’s null, you’re on a “real” terminal. If it contains anything, it’s the name of the screen you’re in.

If you are not in screen:

vinay@dev ~ $ echo $STY vinay@dev ~ $

If you are in screen:

vinay@dev ~ $ echo $STY 2026.pts-0.ip-10-0-1-71

Convert Charset In All Schemas Within An Instance

CONVERT ALL THE THINGS.

Well, almost all the things.

#!/bin/bash
 
for database in aaaaa bbbbb ccccc ddddd eeee
do
        thesetables=`mysql -N -B -e "SELECT CONCAT(TABLE_SCHEMA,'.',TABLE_NAME) \
           FROM information_schema.TABLES where TABLE_SCHEMA = \"$database\"" \
           AND TABLE_SCHEMA NOT IN ('mysql','information_schema','performance_schema')`
        alltables=`echo $alltables $thesetables`
        # change the schema itself
        mysql -e "ALTER DATABASE $database CHARACTER SET utf8 COLLATE utf8_general_ci;"
 
done
 
 
for table in $alltables
do
 
        echo $table
        echo "---------------------------"
        mysql -N -B -e "ALTER TABLE $table DEFAULT CHARACTER set utf8 collate utf8_general_ci;"
        mysql -N -B -e "ALTER TABLE $table CONVERT TO CHARACTER set utf8 collate utf8_general_ci;";
done

Various Queries For Showing User Permissions To Objects

SELECT
   u.usename,
   s.schemaname,
   has_schema_privilege (u.usename, s.schemaname, 'create') AS user_has_select_permission,
   has_schema_privilege (u.usename, s.schemaname, 'usage') AS user_has_usage_permission
FROM
   pg_user u
   CROSS JOIN
      (SELECT DISTINCT
         schemaname
      FROM
         pg_tables) s
WHERE u.usename = 'tim'
   AND s.schemaname = 'dbo';
SELECT
   u.usename,
   t.schemaname || '.' || t.tablename,
   has_table_privilege (u.usename, t.tablename, 'select') AS user_has_select_permission,
   has_table_privilege (u.usename, t.tablename, 'insert') AS user_has_insert_permission,
   has_table_privilege (u.usename, t.tablename, 'update') AS user_has_update_permission,
   has_table_privilege (u.usename, t.tablename, 'delete') AS user_has_delete_permission,
   has_table_privilege (
      u.usename,
      t.tablename,
      'references'
   ) AS user_has_references_permission
FROM
   pg_user u
   CROSS JOIN pg_tables t
WHERE u.usename = 'tim' --    AND t.tablename = 'myTableName'
    AND t.schemaname = 'dbo';
SELECT
   u.usename,
   t.schemaname || '.' || t.tablename,
   has_table_privilege (u.usename, t.tablename, 'select') AS user_has_select_permission,
   has_table_privilege (u.usename, t.tablename, 'insert') AS user_has_insert_permission,
   has_table_privilege (u.usename, t.tablename, 'update') AS user_has_update_permission,
   has_table_privilege (u.usename, t.tablename, 'delete') AS user_has_delete_permission,
   has_table_privilege (
      u.usename,
      t.tablename,
      'references'
   ) AS user_has_references_permission
FROM
   pg_user u
   CROSS JOIN pg_tables t
WHERE --    u.usename = 'tim'
--    AND t.tablename = 'myTableName'
    user_has_insert_permission = 't'
   AND t.schemaname = 'dbo';