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CreateGrid

Function CreateGrid - define/create a new grid file

Calling Sequence  CreateGrid(filename,template)
Parameters
NameTypeDescription

filename stringthe name of the file to store the index
template structure(name = type)template of the data values
Return Type  GridFile
Synopsis Create grid file with given name and record type and return it for subsequent use. The record type defines the type of data to be added to the grid file and is an unevaluated function call of the form Name([name=]type,[name=]type,...). Key fields are given a name by inserting "=" before the type. The name can be later used in queries. Simple field types are: shortint, int, float, double, text. Only simple fields can be used as keys. Composed field types are:

typeexample 

range(type)range(int)excluding range(text)
list(type,type,...)list(float,range(int))excluding list(text)
Examples
> gf := CreateGrid(SPindex, DATA(ID=text,FromOfs=int,ToOfs=int));
gf := GridFile(SPindex, DATA(ID=text(0), FromOfs=int(0), ToOfs=int(0)), record s
ize 10, 0.0 KB in 0 records, 0 buckets, 0.0 % occupancy, 0 buckets read, 0 bucke
ts written)
See also AddGrid,   AllQueryGrid,   CloseGrid,   CompressGrid,   FlushGrid,   GetNextGrid,   GridFile,   MapGrid,   OpenGrid,   QueryGrid,   UncompressGrid