Interface: ParsedQueryIntf

The ParsedQueryIntf is used for interacting with ParsedQueries (e.g. Queries whose fields have been converted into schema indices) This is the primary way in which most of TinyDB Interacts with queries -- routines are provided to get and set expressions and fields, and also to map from named fields into offsets in results for queries

Author:

Sam Madden (madden@cs.berkeley.edu)

Components providing this interface:

tos.lib.TinyDB.ParsedQuery

Components requiring this interface:

tos.lib.TinyDB.AggOperator
tos.lib.TinyDB.DBBufferC
tos.lib.TinyDB.QueryResult
tos.lib.TinyDB.Tuple
tos.lib.TinyDB.TupleRouterM

Commands

• bool queryFieldIsNull(uint8_t field)

  Returns:

  true iff the specified field is null

• Expr getExpr(ParsedQueryPtr q, uint8_t n)

  Returns:

  the nth expression in the parsed query

• ExprPtr getExprPtr(ParsedQueryPtr q, uint8_t n)

  Returns:

  a pointer to the nth expression in the parsed query

• uint8_t getFieldId(ParsedQueryPtr q, uint8_t n)

  Returns:

  the nth field in the parsed query

• result_t setExpr(ParsedQueryPtr q, uint8_t n, Expr e) Set the nth expression in the parsed query

• TuplePtr getTuplePtr(ParsedQueryPtr q)

  Returns:

  a pointer to the start of the tuple stored in a parsed query

• short baseSize(QueryPtr q)

  Returns:

  the size of the parsed query excluding the tuple data corresponding to the specified QueryPtr (used to allocate a parsed query)

• short pqSize(ParsedQueryPtr q)
• uint8_t numResultFields (ParsedQueryPtr q, bool *agg)

• TinyDBError getResultField (ParsedQueryPtr q, QueryResultPtr qr, uint8_t resultid, char *result_buf) Copy data from the field resultid (as returned by getResultId) of qr into result_buf

• TinyDBError getResultId (ParsedQueryPtr q, Field *f, uint8_t *id) Return the index (to be used in getResultField) of the field corresponding to f in this quey.

numResultFields

getResultField

getResultId