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59b6472010
WL#2474 "Multi Range Read: Change the default MRR implementation to implement new MRR interface"
WL#2475 "Batched range read functions for MyISAM/InnoDb"
"Index condition pushdown for MyISAM/InnoDB"
- Adjust test results (checked)
- Code cleanup.
74 lines
2.4 KiB
C++
74 lines
2.4 KiB
C++
/*
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This file contains declarations for
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- Disk-Sweep MultiRangeRead (DS-MRR) implementation
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- Index Condition Pushdown helper functions
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*/
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/**
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A Disk-Sweep MRR interface implementation
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This implementation makes range (and, in the future, 'ref') scans to read
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table rows in disk sweeps.
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Currently it is used by MyISAM and InnoDB. Potentially it can be used with
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any table handler that has non-clustered indexes and on-disk rows.
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*/
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class DsMrr_impl
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{
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public:
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typedef void (handler::*range_check_toggle_func_t)(bool on);
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DsMrr_impl()
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: h2(NULL) {};
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/*
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The "owner" handler object (the one that calls dsmrr_XXX functions.
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It is used to retrieve full table rows by calling rnd_pos().
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*/
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handler *h;
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TABLE *table; /* Always equal to h->table */
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private:
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/* Secondary handler object. It is used for scanning the index */
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handler *h2;
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/* Buffer to store rowids, or (rowid, range_id) pairs */
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uchar *rowids_buf;
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uchar *rowids_buf_cur; /* Current position when reading/writing */
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uchar *rowids_buf_last; /* When reading: end of used buffer space */
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uchar *rowids_buf_end; /* End of the buffer */
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bool dsmrr_eof; /* TRUE <=> We have reached EOF when reading index tuples */
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/* TRUE <=> need range association, buffer holds {rowid, range_id} pairs */
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bool is_mrr_assoc;
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bool use_default_impl; /* TRUE <=> shortcut all calls to default MRR impl */
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public:
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void init(handler *h_arg, TABLE *table_arg)
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{
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h= h_arg;
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table= table_arg;
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}
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int dsmrr_init(handler *h, RANGE_SEQ_IF *seq_funcs, void *seq_init_param,
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uint n_ranges, uint mode, HANDLER_BUFFER *buf);
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void dsmrr_close();
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int dsmrr_fill_buffer();
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int dsmrr_next(char **range_info);
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ha_rows dsmrr_info(uint keyno, uint n_ranges, uint keys, uint *bufsz,
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uint *flags, COST_VECT *cost);
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ha_rows dsmrr_info_const(uint keyno, RANGE_SEQ_IF *seq,
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void *seq_init_param, uint n_ranges, uint *bufsz,
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uint *flags, COST_VECT *cost);
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private:
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bool choose_mrr_impl(uint keyno, ha_rows rows, uint *flags, uint *bufsz,
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COST_VECT *cost);
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bool get_disk_sweep_mrr_cost(uint keynr, ha_rows rows, uint flags,
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uint *buffer_size, COST_VECT *cost);
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};
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void push_index_cond(JOIN_TAB *tab, uint keyno, bool other_tbls_ok);
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