I want a grid around my points(100 x 100 m), where points are center. Creating a grid from
Vector --> Research Tools --> Vector Grid
creates grid, but not centered around my points.
How do I do this?
This way it should work:
Vector -> Geoprocessing Tools -> buffer(s)
There are many way to achieve what you want. Here are a few of them (assuming you want a grid of square cells):
There will be other approaches as well as the above. Just pick one you like that you think will suit your use-case.
Import your data into PostGIS. Create a new geometry column and calculate the vector grid with the ST_Expand function:
Then you can import your data back into QGIS and you will have a vector grid.