Le ven. 3 nov. 2023 à 21:01, Tom Lane <t...@sss.pgh.pa.us> a écrit :
> David Gauthier <dfgpostg...@gmail.com> writes: > > I'm asking about the possibility of indexing portions of a column's value > > where the column has a static field format. > > GIN indexes are meant for exactly that. You might have to write your > own opclass to break up the input values in the way you want though. > > A less difficult answer would be to write a function that breaks up > the input into (say) an array of text and then use the existing > GIN array support. But you'd pay for that by needing to write more > complicated queries to use the index. > > regards, tom lane > > > Hello David, Reading your mail, it seems that your data column contains 3 different kinds of atomic information: * Characters 1-2 * Characters 3-4 * Characters 5-8 Does it make sense to split this data into 3 separate columns? Each one could be indexed, and you can rebuild the original thanks to a generated column: https://www.postgresql.org/docs/current/ddl-generated-columns.html HTH, Thomas