OLAP Object Queries : Fields Parameter : Basic Formats
Basic Formats
The fields parameter has the following general formats:
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*: Using the value “*” (without quotes) is a synonym for omitting the fields parameter. All scalar fields are returned for each object.
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_all: This keyword requests all scalar fields of each perspective object and the scalar fields of each first-level object connected via a link value.
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_local: This keyword requests all scalar field values and the _ID value of all link fields for each object.
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<scalar field>: When a scalar field is requested, its value (SV) or values (MV), if any, are returned.
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<link field>: When a link field is requested, the _ID of each linked object is returned.
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<group field>: When a group field is requested, all leaf scalar and link fields within the group and its nested groups, recursively, are returned.
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f1,f2,f3: The fields parameter can be a comma-separated list of field names. This example is a simple list of names: only fields f1, f2, and f3 are returned. Each field can be a scalar, link, or group field.
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f1,f2.f3,f2.f4.f5: This example uses dotted notation to define link paths. This example requests three fields: f1, which belongs to the perspective object; f3, which is connected to the perspective object via link f2; and f5, which is related via links f2 to f4. When dotted notation is used, each field to the left of a dot must be a link or xlink belonging to the object on its left.
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f=f1,f2(f3,f4(f5)): This is the same example as above using parenthetical qualification instead of dotted notation. Parenthetical and dotted notations can be mixed within a single fields parameter list. Example: f=Name,Manager(Name,Manager.Name).
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f1[s1],f2[s2].f3[s3],f2.f4[s4].f5: This is a dotted notation example where size limits are placed on specific link fields. If f1 is a link field, the number of f1 values returned for each object will be no more than s1, which must be a number. Similarly, link f2 is limited to s2 values per object; f3 is limited to s3 values for each f2 value; and f4 is limited to s4 values per f2 value. Since it has no bracketed parameter, field f5 is not limited in the number of values returned. Link size limits are explained further later.
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f=f1[s1],f2[s2](f3[s3],f4[s4](f5)): This is the same size limits example as above using parenthetical qualification instead of dotted notation. Link size limits are explained further later.