Group records with same value in one row informix
You are actually looking for PIVOT TABLE which seems to not be possible in Informix (I think, just by googling it, I don't know Informix). The CASE workaround, presentet e.g. here would mean that you would need a special CASE for each date... which seems pretty ugly (but you can do it).

What I would recommend, is to query the table in the "tall format" (also called "wide") and do the pivoting (wide format) transformation in the programming language, from which you call the database from. For example, I use R programmiing language a lot, and in R, I use the dcast or acast or cast function from reshape2 library to reshape the data. Just google it for your language:


  how to make pivot table in [[whatever-programming-language-you-use]]


or 


  convert long table to wide table in [[whatever-programming-language-you-use]]