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/******************************************************
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Caching of externally stored column prefixes
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Created September 2006 Marko Makela
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*******************************************************/
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#include "row0types.h"
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#include "data0types.h"
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/************************************************************************
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Creates a cache of column prefixes of externally stored columns. */
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/* out,own: column prefix cache */
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ulint n_ext, /* in: number of externally stored columns */
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const ulint* ext, /* in: col_no's of externally stored columns
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in the InnoDB table object, as reported by
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dict_col_get_no(); NOT relative to the records
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in the clustered index */
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const dtuple_t* tuple, /* in: data tuple containing the field
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references of the externally stored
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columns; must be indexed by col_no;
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the clustered index record must be
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covered by a lock or a page latch
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to prevent deletion (rollback or purge). */
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ulint zip_size,/* compressed page size in bytes, or 0 */
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mem_heap_t* heap); /* in: heap where created */
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/************************************************************************
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Looks up a column prefix of an externally stored column. */
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/* out: column prefix, or NULL if
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the column is not stored externally,
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or pointer to field_ref_zero
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if the BLOB pointer is unset */
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const row_ext_t* ext, /* in/out: column prefix cache */
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ulint i, /* in: index of ext->ext[] */
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ulint* len); /* out: length of prefix, in bytes,
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at most REC_MAX_INDEX_COL_LEN */
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/************************************************************************
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Looks up a column prefix of an externally stored column. */
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/* out: column prefix, or NULL if
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the column is not stored externally,
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or pointer to field_ref_zero
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if the BLOB pointer is unset */
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const row_ext_t* ext, /* in: column prefix cache */
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ulint col, /* in: column number in the InnoDB
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table object, as reported by
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dict_col_get_no(); NOT relative to the
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records in the clustered index */
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ulint* len); /* out: length of prefix, in bytes,
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at most REC_MAX_INDEX_COL_LEN */
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/* Prefixes of externally stored columns */
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struct row_ext_struct{
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ulint n_ext; /* number of externally stored columns */
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const ulint* ext; /* col_no's of externally stored columns */
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byte* buf; /* backing store of the column prefix cache */
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ulint len[1]; /* prefix lengths; 0 if not cached */
added
removed
storage/innobase/include/row0ext.h
