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C H A P T E R 1 1
Data Storage and Retrieval
Summary of Data Storage
11-69
Multiple-Slot Index Specification Frame
11
{
// index keys may be multiple slot values
structure: 'multiSlot, // must use this value
// up to six path expressions specifying indexed slots
path:[
pathExpr1
,
pathExpr2
, ... ,
pathExpr6
],
// data type found in each indexed slot
type:[
sym1
,
sym2
, ...
sym6
]
// optional. 'ascending or 'descending
order: [
sym1
,
sym2
, ...
sym6
]
// optional. pass 1 to use alternate sort table
sortID: nil
}
Tags Index Specification Frame
11
{
// must use this value - tags are slot values
structure:'slot,
// index values (tags) extracted from this slot
path:'
slotName
,
// must use this value
type:'tags,
}
Query Specification Frame
11
// pass nil instead of a query spec frame
// to retrieve all entries in the soup
// this frame used for queries on single-slot indexes
// see next example for multiple-slot query spec frame
{
// use the specified single-slot index for this query
// required when querying for index values
indexPath : '
pathExpr
,
// minimum index key value examined by this query
// for all entries, (beginKey
entry.indexPath)
beginKey :
keyValue
, // optional
// excluded lower boundary of key range examined by query
// for all entries, (beginExclKey < entry.indexPath)
beginExclKey :
keyValue
, // optional
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