I have tried
sudo apt-get update (it is working fine)
After that when i do
sudo apt-get upgrade this error is displaying:
Reading package lists... Done Building dependency tree Reading state information... Done You might want to run 'apt --fix-broken install' to correct these. The following packages have unmet dependencies: mariadb-server-10.3 : Depends: mariadb-client-10.3 (>= 1:10.3.34+maria~focal) but 1:10.3.34-0ubuntu0.20.04.1 is installed mariadb-server-core-10.3 : Breaks: mariadb-client-10.3 (< 1:10.3.34+maria~focal) but 1:10.3.34-0ubuntu0.20.04.1 is installed E: Unmet dependencies. Try 'apt --fix-broken install' with no packages (or specify a solution).
I tried this command
sudo apt --fix-broken install Reading package lists... Done Building dependency tree Reading state information... Done Correcting dependencies... Done The following packages were automatically installed and are no longer required: chromium-codecs-ffmpeg-extra gstreamer1.0-vaapi libconfig-inifiles-perl libgstreamer-plugins-bad1.0-0 libva-wayland2 Use 'sudo apt autoremove' to remove them. The following additional packages will be installed: mariadb-client-10.3 mariadb-client-core-10.3 The following packages will be upgraded: mariadb-client-10.3 mariadb-client-core-10.3 2 upgraded, 0 newly installed, 0 to remove and 139 not upgraded. 4 not fully installed or removed. Need to get 0 B/1,866 kB of archives. After this operation, 20.1 MB disk space will be freed. Do you want to continue? [Y/n] y dpkg: regarding .../mariadb-client-core-10.3_1%3a10.3.34+maria~focal_amd64.deb c ontaining mariadb-client-core-10.3: mariadb-client-10.3 conflicts with mysql-client-core-5.5 mariadb-client-core-10.3 provides mysql-client-core-5.5 and is to be installed . dpkg: error processing archive /var/cache/apt/archives/mariadb-client-core-10.3_ 1%3a10.3.34+maria~focal_amd64.deb (--unpack): conflicting packages - not installing mariadb-client-core-10.3 dpkg: regarding .../mariadb-client-10.3_1%3a10.3.34+maria~focal_amd64.deb contai ning mariadb-client-10.3: mariadb-client-core-10.3 conflicts with mysql-client-5.5 mariadb-client-10.3 provides mysql-client-5.5 and is to be installed. dpkg: error processing archive /var/cache/apt/archives/mariadb-client-10.3_1%3a1 0.3.34+maria~focal_amd64.deb (--unpack): conflicting packages - not installing mariadb-client-10.3 Errors were encountered while processing: /var/cache/apt/archives/mariadb-client-core-10.3_1%3a10.3.34+maria~focal_amd64. deb /var/cache/apt/archives/mariadb-client-10.3_1%3a10.3.34+maria~focal_amd64.deb E: Sub-process /usr/bin/dpkg returned an error code (1)