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/******************************************************
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Created 12/19/1997 Heikki Tuuri
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*******************************************************/
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#include "data0data.h"
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#include "que0types.h"
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#include "dict0types.h"
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#include "trx0types.h"
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#include "row0types.h"
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#include "que0types.h"
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#include "read0read.h"
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#include "row0mysql.h"
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/*************************************************************************
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Creates a select node struct. */
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/* out, own: select node struct */
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mem_heap_t* heap); /* in: memory heap where created */
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/*************************************************************************
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Frees the memory private to a select node when a query graph is freed,
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does not free the heap where the node was originally created. */
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sel_node_free_private(
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/*==================*/
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sel_node_t* node); /* in: select node struct */
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/*************************************************************************
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Frees a prefetch buffer for a column, including the dynamically allocated
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memory for data stored there. */
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sel_col_prefetch_buf_free(
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/*======================*/
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sel_buf_t* prefetch_buf); /* in, own: prefetch buffer */
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/*************************************************************************
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Gets the plan node for the nth table in a join. */
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sel_node_get_nth_plan(
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/*==================*/
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/**************************************************************************
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Performs a select step. This is a high-level function used in SQL execution
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/* out: query thread to run next or NULL */
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que_thr_t* thr); /* in: query thread */
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/**************************************************************************
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Performs an execution step of an open or close cursor statement node. */
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/* out: query thread to run next or NULL */
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que_thr_t* thr); /* in: query thread */
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/**************************************************************************
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Performs a fetch for a cursor. */
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/* out: query thread to run next or NULL */
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que_thr_t* thr); /* in: query thread */
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/********************************************************************
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Sample callback function for fetch that prints each row.*/
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/* out: always returns non-NULL */
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void* row, /* in: sel_node_t* */
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void* user_arg); /* in: not used */
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/********************************************************************
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Callback function for fetch that stores an unsigned 4 byte integer to the
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location pointed. The column's type must be DATA_INT, DATA_UNSIGNED, length
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row_fetch_store_uint4(
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/*==================*/
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/* out: always returns NULL */
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void* row, /* in: sel_node_t* */
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void* user_arg); /* in: data pointer */
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/***************************************************************
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Prints a row in a select result. */
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/* out: query thread to run next or NULL */
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que_thr_t* thr); /* in: query thread */
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/********************************************************************
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Converts a key value stored in MySQL format to an Innobase dtuple. The last
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field of the key value may be just a prefix of a fixed length field: hence
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the parameter key_len. But currently we do not allow search keys where the
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last field is only a prefix of the full key field len and print a warning if
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row_sel_convert_mysql_key_to_innobase(
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/*==================================*/
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dtuple_t* tuple, /* in: tuple where to build;
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NOTE: we assume that the type info
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in the tuple is already according
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byte* buf, /* in: buffer to use in field
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ulint buf_len, /* in: buffer length */
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dict_index_t* index, /* in: index of the key value */
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byte* key_ptr, /* in: MySQL key value */
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ulint key_len, /* in: MySQL key value length */
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trx_t* trx); /* in: transaction */
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/************************************************************************
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Searches for rows in the database. This is used in the interface to
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MySQL. This function opens a cursor, and also implements fetch next
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and fetch prev. NOTE that if we do a search with a full key value
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from a unique index (ROW_SEL_EXACT), then we will not store the cursor
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position and fetch next or fetch prev must not be tried to the cursor! */
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row_search_for_mysql(
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/*=================*/
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DB_END_OF_INDEX, DB_DEADLOCK,
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or DB_TOO_BIG_RECORD */
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byte* buf, /* in/out: buffer for the fetched
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row in the MySQL format */
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ulint mode, /* in: search mode PAGE_CUR_L, ... */
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row_prebuilt_t* prebuilt, /* in: prebuilt struct for the
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table handle; this contains the info
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of search_tuple, index; if search
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tuple contains 0 fields then we
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position the cursor at the start or
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the end of the index, depending on
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ulint match_mode, /* in: 0 or ROW_SEL_EXACT or
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ROW_SEL_EXACT_PREFIX */
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ulint direction); /* in: 0 or ROW_SEL_NEXT or
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ROW_SEL_PREV; NOTE: if this is != 0,
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then prebuilt must have a pcur
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with stored position! In opening of a
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cursor 'direction' should be 0. */
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/***********************************************************************
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Checks if MySQL at the moment is allowed for this table to retrieve a
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consistent read result, or store it to the query cache. */
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row_search_check_if_query_cache_permitted(
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/*======================================*/
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/* out: TRUE if storing or retrieving
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from the query cache is permitted */
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trx_t* trx, /* in: transaction object */
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const char* norm_name); /* in: concatenation of database name,
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'/' char, table name */
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/***********************************************************************
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Read the max AUTOINC value from an index. */
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row_search_max_autoinc(
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/*===================*/
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/* out: DB_SUCCESS if all OK else
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dict_index_t* index, /* in: index to search */
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const char* col_name, /* in: autoinc column name */
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ib_longlong* value); /* out: AUTOINC value read */
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/* A structure for caching column values for prefetched rows */
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struct sel_buf_struct{
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byte* data; /* data, or NULL; if not NULL, this field
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has allocated memory which must be explicitly
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freed; can be != NULL even when len is
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ulint len; /* data length or UNIV_SQL_NULL */
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/* size of memory buffer allocated for data:
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this can be more than len; this is defined
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dict_table_t* table; /* table struct in the dictionary
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dict_index_t* index; /* table index used in the search */
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btr_pcur_t pcur; /* persistent cursor used to search
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ibool asc; /* TRUE if cursor traveling upwards */
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ibool pcur_is_open; /* TRUE if pcur has been positioned
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and we can try to fetch new rows */
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ibool cursor_at_end; /* TRUE if the cursor is open but
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we know that there are no more
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qualifying rows left to retrieve from
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the index tree; NOTE though, that
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there may still be unprocessed rows in
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the prefetch stack; always FALSE when
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pcur_is_open is FALSE */
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ibool stored_cursor_rec_processed;
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/* TRUE if the pcur position has been
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stored and the record it is positioned
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on has already been processed */
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que_node_t** tuple_exps; /* array of expressions which are used
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to calculate the field values in the
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search tuple: there is one expression
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for each field in the search tuple */
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dtuple_t* tuple; /* search tuple */
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ulint mode; /* search mode: PAGE_CUR_G, ... */
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ulint n_exact_match; /* number of first fields in the search
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tuple which must be exactly matched */
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ibool unique_search; /* TRUE if we are searching an
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index record with a unique key */
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ulint n_rows_fetched; /* number of rows fetched using pcur
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after it was opened */
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ulint n_rows_prefetched;/* number of prefetched rows cached
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for fetch: fetching several rows in
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the same mtr saves CPU time */
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ulint first_prefetched;/* index of the first cached row in
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select buffer arrays for each column */
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ibool no_prefetch; /* no prefetch for this table */
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sym_node_list_t columns; /* symbol table nodes for the columns
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to retrieve from the table */
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UT_LIST_BASE_NODE_T(func_node_t)
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end_conds; /* conditions which determine the
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fetch limit of the index segment we
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have to look at: when one of these
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fails, the result set has been
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exhausted for the cursor in this
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index; these conditions are normalized
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so that in a comparison the column
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for this table is the first argument */
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UT_LIST_BASE_NODE_T(func_node_t)
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other_conds; /* the rest of search conditions we can
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test at this table in a join */
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ibool must_get_clust; /* TRUE if index is a non-clustered
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index and we must also fetch the
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clustered index record; this is the
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case if the non-clustered record does
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not contain all the needed columns, or
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if this is a single-table explicit
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cursor, or a searched update or
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ulint* clust_map; /* map telling how clust_ref is built
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from the fields of a non-clustered
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dtuple_t* clust_ref; /* the reference to the clustered
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index entry is built here if index is
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a non-clustered index */
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btr_pcur_t clust_pcur; /* if index is non-clustered, we use
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this pcur to search the clustered
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mem_heap_t* old_vers_heap; /* memory heap used in building an old
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version of a row, or NULL */
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struct sel_node_struct{
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que_common_t common; /* node type: QUE_NODE_SELECT */
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ulint state; /* node state */
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que_node_t* select_list; /* select list */
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sym_node_t* into_list; /* variables list or NULL */
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sym_node_t* table_list; /* table list */
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ibool asc; /* TRUE if the rows should be fetched
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in an ascending order */
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ibool set_x_locks; /* TRUE if the cursor is for update or
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delete, which means that a row x-lock
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should be placed on the cursor row */
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ibool select_will_do_update;
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/* TRUE if the select is for a searched
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update which can be performed in-place:
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in this case the select will take care
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ulint latch_mode; /* BTR_SEARCH_LEAF, or BTR_MODIFY_LEAF
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if select_will_do_update is TRUE */
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ulint row_lock_mode; /* LOCK_X or LOCK_S */
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ulint n_tables; /* number of tables */
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ulint fetch_table; /* number of the next table to access
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plan_t* plans; /* array of n_tables many plan nodes
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containing the search plan and the
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search data structures */
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que_node_t* search_cond; /* search condition */
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read_view_t* read_view; /* if the query is a non-locking
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consistent read, its read view is
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placed here, otherwise NULL */
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ibool consistent_read;/* TRUE if the select is a consistent,
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order_node_t* order_by; /* order by column definition, or
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ibool is_aggregate; /* TRUE if the select list consists of
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aggregate functions */
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ibool aggregate_already_fetched;
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/* TRUE if the aggregate row has
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already been fetched for the current
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ibool can_get_updated;/* this is TRUE if the select
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is in a single-table explicit
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cursor which can get updated
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within the stored procedure,
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or in a searched update or
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delete; NOTE that to determine
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of an explicit cursor if it
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can get updated, the parser
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checks from a stored procedure
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if it contains positioned
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update or delete statements */
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sym_node_t* explicit_cursor;/* not NULL if an explicit cursor */
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UT_LIST_BASE_NODE_T(sym_node_t)
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copy_variables; /* variables whose values we have to
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copy when an explicit cursor is opened,
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so that they do not change between
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/* Select node states */
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#define SEL_NODE_CLOSED 0 /* it is a declared cursor which is not
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#define SEL_NODE_OPEN 1 /* intention locks not yet set on
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#define SEL_NODE_FETCH 2 /* intention locks have been set */
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#define SEL_NODE_NO_MORE_ROWS 3 /* cursor has reached the result set
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/* Fetch statement node */
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struct fetch_node_struct{
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que_common_t common; /* type: QUE_NODE_FETCH */
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sel_node_t* cursor_def; /* cursor definition */
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sym_node_t* into_list; /* variables to set */
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func; /* User callback function or NULL.
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The first argument to the function
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is a sel_node_t*, containing the
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results of the SELECT operation for
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one row. If the function returns
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NULL, it is not interested in
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further rows and the cursor is
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modified so (cursor % NOTFOUND) is
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true. If it returns not-NULL,
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continue normally. See
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row_fetch_print() for an example
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(and a useful debugging tool). */
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/* Open or close cursor statement node */
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struct open_node_struct{
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que_common_t common; /* type: QUE_NODE_OPEN */
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ulint op_type; /* ROW_SEL_OPEN_CURSOR or
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ROW_SEL_CLOSE_CURSOR */
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sel_node_t* cursor_def; /* cursor definition */
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/* Row printf statement node */
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struct row_printf_node_struct{
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que_common_t common; /* type: QUE_NODE_ROW_PRINTF */
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sel_node_t* sel_node; /* select */
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#define ROW_SEL_OPEN_CURSOR 0
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#define ROW_SEL_CLOSE_CURSOR 1
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/* Flags for the MySQL interface */
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#define ROW_SEL_NEXT 1
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#define ROW_SEL_PREV 2
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#define ROW_SEL_EXACT 1 /* search using a complete key value */
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#define ROW_SEL_EXACT_PREFIX 2 /* search using a key prefix which
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must match to rows: the prefix may
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contain an incomplete field (the
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last field in prefix may be just
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a prefix of a fixed length column) */
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#include "row0sel.ic"
added
removed
storage/innobase/include/row0sel.h
