Merge branch 'master' of git.ducamps.win:vincent/notebook

IT/SQL/PostgreSQL/Upgrade.md

@@ -26,3 +26,20 @@ pg_upgrade -b /opt/pgsql-PG_VERSION/bin -B /usr/bin -d /var/lib/postgres/olddata
 ```
 - check both pg_hba.conf in new  and old cluster
 - restart server `sc-start postgresql`
+
+# sequece manipulation
+
+sequence are use to generate uniq identifier
+- get sequence value
+```SQL
+select * from name_seq;
+```
+- increment sequence value
+```SQL
+select nextval(name_seq);
+```
+
+- set sequence value:
+```SQL
+select setval(name_seq,newvalue);
+```

IT/git/Git.md

@@ -23,8 +23,22 @@ this will ask if you want to add each modification with this option:
 ## delete a file from complete history
 
 be carefull can't push repo last time use
+need to be in a repo with no modification
 
-`git filter-branch --tree-filter 'rm -f passwords.txt' HEAD`
+```
+git filter-branch --index-filter "git rm -rf --cached --ignore-unmatch $file" HEAD 
+rm -rf .git/refs/original/ && git reflog expire --all &&  git gc --aggressive --prune
+```
+
+## create a repo from other repo subfoler
+
+- clone the first repo
+- go in this directory
+- launch
+```
+git filter-branch --prune-empty --subdirectory-filter "subdirectory/path" master
+```
+- push in your new git repo
 
 ## changing email adress