Create read only user on Postgres

GRANT SELECT ON ALL TABLES IN SCHEMA public TO username;

ALTER DEFAULT PRIVILEGES IN SCHEMA public
GRANT SELECT ON TABLES TO username;

pgAdmin 4 bug when install Python 3

pgAdmin 4 has bug table_oid on query check it https://stackoverflow.com/questions/57226520/select-does-not-return-values-postgres-11-4

insufficient permissions for device

retrieving device properties for ro.product.cpu.abi:
error: insufficient permissions for device: user in plugdev group; are your udev rules wrong?

--> change Charge devic to PTP on USB config of Phone

Remove watermark pdf

pdftops in.pdf - | sed 's/WATERMARK//' | ps2pdf - out.pdf

Oracl basics

source /u01/app/oracle/product/11.2.0/xe/bin/oracle_env.sh

/etc/init.d/oracle-xe start

/etc/init.d/oracle-xe stop

sqlplus / as sysdba

Scale Firefox and Chrome on HIDPI

Firefox:
about:config
layout.css.devPixelsPerPx --> change value from 1.5 to 3

Chrome
Open a terminal 

sudo gedit /usr/share/applications/google-chrome.desktop

Find this line:

Exec=/usr/bin/google-chrome-stable %U

Change n into 1.5 to 3:

Exec=/usr/bin/google-chrome-stable --force-device-scale-factor=n %U

Save/close, relaunch Chrome.

Change owner all database objects to new role

for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" DBNAME` ; do  psql -c "alter table \"$tbl\" owner to NEWUSER" DBNAME ; done

for tbl in `psql -qAt -c "select sequence_name from information_schema.sequences where sequence_schema = 'public';" DBNAME` ; do  psql -c "alter table \"$tbl\" owner to NEWUSER" DBNAME ; done

for tbl in `psql -qAt -c "select table_name from information_schema.views where table_schema = 'public';" DBNAME` ; do  psql -c "alter table \"$tbl\" owner to NEWUSER" DBNAME ; done