pars0pars.c

这是linux下运行的mysql软件包,可用于linux 下安装 php + mysql + apach 的网络配置

			col_node = sym_tab_add_id(pars_sym_tab_global,
						(byte*)col->name,
						ut_strlen(col->name));
			select_node->select_list
					= que_node_list_add_last(
						select_node->select_list,
								col_node);
		}

		table_node = que_node_get_next(table_node);
	}
}

/*************************************************************************
Parses a select list; creates a query graph node for the whole SELECT
statement. */

sel_node_t*
pars_select_list(
/*=============*/
					/* out, own: select node in a query
					tree */
	que_node_t*	select_list,	/* in: select list */
	sym_node_t*	into_list)	/* in: variables list or NULL */
{
	sel_node_t*	node;

	node = sel_node_create(pars_sym_tab_global->heap);
	
	node->select_list = select_list;
	node->into_list = into_list;

	pars_resolve_exp_list_variables_and_types(NULL, into_list);

	return(node);
}

/*************************************************************************
Checks if the query is an aggregate query, in which case the selct list must
contain only aggregate function items. */
static
void
pars_check_aggregate(
/*=================*/
	sel_node_t*	select_node)	/* in: select node already containing
					the select list */
{
	que_node_t*	exp_node;
	func_node_t*	func_node;
	ulint		n_nodes			= 0;
	ulint		n_aggregate_nodes	= 0;

	exp_node = select_node->select_list;

	while (exp_node) {

		n_nodes++;
	
		if (que_node_get_type(exp_node) == QUE_NODE_FUNC) {

			func_node = exp_node;

			if (func_node->class == PARS_FUNC_AGGREGATE) {

				n_aggregate_nodes++;
			}
		}

		exp_node = que_node_get_next(exp_node);
	}

	if (n_aggregate_nodes > 0) {
		ut_a(n_nodes == n_aggregate_nodes);

		select_node->is_aggregate = TRUE;
	} else {
		select_node->is_aggregate = FALSE;
	}
}

/*************************************************************************
Parses a select statement. */

sel_node_t*
pars_select_statement(
/*==================*/
					/* out, own: select node in a query
					tree */
	sel_node_t*	select_node,	/* in: select node already containing
					the select list */
	sym_node_t*	table_list,	/* in: table list */
	que_node_t*	search_cond,	/* in: search condition or NULL */
	pars_res_word_t* for_update,	/* in: NULL or &pars_update_token */
	pars_res_word_t* consistent_read,/* in: NULL or
						&pars_consistent_token */
	order_node_t*	order_by)	/* in: NULL or an order-by node */
{
	select_node->state = SEL_NODE_OPEN;

	select_node->table_list = table_list;
	select_node->n_tables = pars_retrieve_table_list_defs(table_list);

	if (select_node->select_list == &pars_star_denoter) {

		/* SELECT * FROM ... */
		pars_select_all_columns(select_node);
	}
	
	if (select_node->into_list) {
		ut_a(que_node_list_get_len(select_node->into_list)
			== que_node_list_get_len(select_node->select_list));
	}

	UT_LIST_INIT(select_node->copy_variables);

	pars_resolve_exp_list_columns(table_list, select_node->select_list);
	pars_resolve_exp_list_variables_and_types(select_node,
						select_node->select_list);
	pars_check_aggregate(select_node);

	select_node->search_cond = search_cond;

	if (search_cond) {
		pars_resolve_exp_columns(table_list, search_cond);
		pars_resolve_exp_variables_and_types(select_node, search_cond);
	}

	if (for_update) {
		ut_a(!consistent_read);
		select_node->set_x_locks = TRUE;
		select_node->row_lock_mode = LOCK_X;
	} else {
		select_node->set_x_locks = FALSE;
		select_node->row_lock_mode = LOCK_S;
	}

	if (consistent_read) {
		select_node->consistent_read = TRUE;
	} else {
		select_node->consistent_read = FALSE;
		select_node->read_view = NULL;
	}

	select_node->order_by = order_by;

	if (order_by) {
		pars_resolve_exp_columns(table_list, order_by->column);
	}
	
	/* The final value of the following fields depend on the environment
	where the select statement appears: */

	select_node->can_get_updated = FALSE;
	select_node->explicit_cursor = NULL;

	opt_search_plan(select_node);

	return(select_node);
}

/*************************************************************************
Parses a cursor declaration. */

que_node_t*
pars_cursor_declaration(
/*====================*/
					/* out: sym_node */
	sym_node_t*	sym_node,	/* in: cursor id node in the symbol
					table */
	sel_node_t*	select_node)	/* in: select node */
{
	sym_node->resolved = TRUE;
	sym_node->token_type = SYM_CURSOR;
	sym_node->cursor_def = select_node;

	select_node->state = SEL_NODE_CLOSED;
	select_node->explicit_cursor = sym_node;

	return(sym_node);	
}

/*************************************************************************
Parses a delete or update statement start. */

upd_node_t*
pars_update_statement_start(
/*========================*/
					/* out, own: update node in a query
					tree */
	ibool		is_delete,	/* in: TRUE if delete */
	sym_node_t*	table_sym,	/* in: table name node */
	col_assign_node_t* col_assign_list)/* in: column assignment list, NULL
					if delete */	
{
	upd_node_t*	node;
	
	node = upd_node_create(pars_sym_tab_global->heap);

	node->is_delete = is_delete;

	node->table_sym = table_sym;
	node->col_assign_list = col_assign_list;

	return(node);
}
	
/*************************************************************************
Parses a column assignment in an update. */

col_assign_node_t*
pars_column_assignment(
/*===================*/
				/* out: column assignment node */
	sym_node_t*	column,	/* in: column to assign */
	que_node_t*	exp)	/* in: value to assign */
{
	col_assign_node_t*	node;

	node = mem_heap_alloc(pars_sym_tab_global->heap,
						sizeof(col_assign_node_t));
	node->common.type = QUE_NODE_COL_ASSIGNMENT;

	node->col = column;
	node->val = exp;

	return(node);
}

/*************************************************************************
Processes an update node assignment list. */
static
void
pars_process_assign_list(
/*=====================*/
	upd_node_t*	node)	/* in: update node */
{
	col_assign_node_t*	col_assign_list;
	sym_node_t*		table_sym;
	col_assign_node_t*	assign_node;
	upd_field_t*		upd_field;
	dict_index_t*		clust_index;
	sym_node_t*		col_sym;
	ulint			changes_ord_field;
	ulint			changes_field_size;
	ulint			n_assigns;
	ulint			i;

	table_sym = node->table_sym;
	col_assign_list = node->col_assign_list;
	clust_index = dict_table_get_first_index(node->table);
	
	assign_node = col_assign_list;
	n_assigns = 0;

	while (assign_node) {
		pars_resolve_exp_columns(table_sym, assign_node->col);
		pars_resolve_exp_columns(table_sym, assign_node->val);
		pars_resolve_exp_variables_and_types(NULL, assign_node->val);

		/* ut_a(dtype_get_mtype(dfield_get_type(
				que_node_get_val(assign_node->col)))
		     == dtype_get_mtype(dfield_get_type(
				que_node_get_val(assign_node->val)))); */

		/* Add to the update node all the columns found in assignment
		values as columns to copy: therefore, TRUE */

		opt_find_all_cols(TRUE, clust_index, &(node->columns), NULL,
							assign_node->val);
		n_assigns++;

		assign_node = que_node_get_next(assign_node);
	}

	node->update = upd_create(n_assigns, pars_sym_tab_global->heap);

	assign_node = col_assign_list;

	changes_field_size = UPD_NODE_NO_SIZE_CHANGE;

	for (i = 0; i < n_assigns; i++) {
		upd_field = upd_get_nth_field(node->update, i);

		col_sym = assign_node->col;

		upd_field_set_field_no(upd_field,
				dict_index_get_nth_col_pos(clust_index,
							col_sym->col_no),
							clust_index, NULL);
		upd_field->exp = assign_node->val;

		if (!dtype_is_fixed_size(
			dict_index_get_nth_type(clust_index,
						upd_field->field_no))) {
			changes_field_size = 0;
		}					
		
		assign_node = que_node_get_next(assign_node);
	}

	/* Find out if the update can modify an ordering field in any index */

	changes_ord_field = UPD_NODE_NO_ORD_CHANGE;

	if (row_upd_changes_some_index_ord_field_binary(node->table,
							node->update)) {
		changes_ord_field = 0;
	}
	
	node->cmpl_info = changes_ord_field | changes_field_size;
}
	
/*************************************************************************
Parses an update or delete statement. */

upd_node_t*
pars_update_statement(
/*==================*/
					/* out, own: update node in a query
					tree */
	upd_node_t*	node,		/* in: update node */
	sym_node_t*	cursor_sym,	/* in: pointer to a cursor entry in
					the symbol table or NULL */
	que_node_t*	search_cond)	/* in: search condition or NULL */
{
	sym_node_t*	table_sym;
	sel_node_t*	sel_node;
	plan_t*		plan;

	table_sym = node->table_sym;
	
	pars_retrieve_table_def(table_sym);
	node->table = table_sym->table;

	UT_LIST_INIT(node->columns);
	
	/* Make the single table node into a list of table nodes of length 1 */
	
	que_node_list_add_last(NULL, table_sym);

	if (cursor_sym) {
		pars_resolve_exp_variables_and_types(NULL, cursor_sym);

		sel_node = cursor_sym->alias->cursor_def;

		node->searched_update = FALSE;
	} else {
		sel_node = pars_select_list(NULL, NULL);

		pars_select_statement(sel_node, table_sym, search_cond, NULL,
								NULL, NULL);
		node->searched_update = TRUE;
		sel_node->common.parent = node;
	}
	
	node->select = sel_node;

	ut_a(!node->is_delete || (node->col_assign_list == NULL));
	ut_a(node->is_delete || (node->col_assign_list != NULL));

	if (node->is_delete) {
		node->cmpl_info = 0;
	} else {
		pars_process_assign_list(node);
	}

	if (node->searched_update) {
		node->has_clust_rec_x_lock = TRUE;
		sel_node->set_x_locks = TRUE;
		sel_node->row_lock_mode = LOCK_X;
	} else {
		node->has_clust_rec_x_lock = sel_node->set_x_locks;
	}

	ut_a(sel_node->n_tables == 1);
	ut_a(sel_node->consistent_read == FALSE);
	ut_a(sel_node->order_by == NULL);
	ut_a(sel_node->is_aggregate == FALSE);

	sel_node->can_get_updated = TRUE;
	
	node->state = UPD_NODE_UPDATE_CLUSTERED;
	
	plan = sel_node_get_nth_plan(sel_node, 0);

	plan->no_prefetch = TRUE;

	if (!((plan->index)->type & DICT_CLUSTERED)) {

		plan->must_get_clust = TRUE;

		node->pcur = &(plan->clust_pcur);
	} else {
		node->pcur = &(plan->pcur);
	}

	if (!node->is_delete && node->searched_update
			&& (node->cmpl_info & UPD_NODE_NO_SIZE_CHANGE)
			&& (node->cmpl_info & UPD_NODE_NO_ORD_CHANGE)) {

		/* The select node can perform the update in-place */

		ut_a(plan->asc);

		node->select_will_do_update = TRUE;
		sel_node->select_will_do_update = TRUE;
		sel_node->latch_mode = BTR_MODIFY_LEAF;
	}

	return(node);
}

/*************************************************************************
Parses an insert statement. */

ins_node_t*
pars_insert_statement(
/*==================*/
					/* out, own: update node in a query
					tree */
	sym_node_t*	table_sym,	/* in: table name node */
	que_node_t* 	values_list,	/* in: value expression list or NULL */
	sel_node_t*	select)		/* in: select condition or NULL */
{
	ins_node_t*	node;
	dtuple_t*	row;
	ulint		ins_type;

	ut_a(values_list || select);
	ut_a(!values_list || !select);

	if (values_list) {
		ins_type = INS_VALUES;
	} else {
		ins_type = INS_SEARCHED;
	}

	pars_retrieve_table_def(table_sym);

	node = ins_node_create(ins_type, table_sym->table,
						pars_sym_tab_global->heap);

	row = dtuple_create(pars_sym_tab_global->heap,
					dict_table_get_n_cols(node->table));

	dict_table_copy_types(row, table_sym->table);

	ins_node_set_new_row(node, row);

	node->select = select;

	if (select) {
		select->common.parent = node;

		ut_a(que_node_list_get_len(select->select_list)
			== dict_table_get_n_user_cols(table_sym->table));
	}
	
	node->values_list = values_list;

	if (node->values_list) {
		pars_resolve_exp_list_variables_and_types(NULL, values_list);

		ut_a(que_node_list_get_len(values_list)
			== dict_table_get_n_user_cols(table_sym->table));
	}

	return(node);
}

/*************************************************************************
Set the type of a dfield. */
static
void
pars_set_dfield_type(
/*=================*/
	dfield_t*	dfield,	/* in: dfield */
	pars_res_word_t* type)	/* in: pointer to a type token */
{
	if (type == &pars_int_token) {

		dtype_set(dfield_get_type(dfield), DATA_INT, 0, 4, 0);

	} else if (type == &pars_char_token) {

		dtype_set(dfield_get_type(dfield), DATA_VARCHAR,
							DATA_ENGLISH, 0, 0);
	} else {
		ut_error;
	}
}

/*************************************************************************
Parses a variable declaration. */

sym_node_t*
pars_variable_declaration(
/*======================*/
				/* out, own: symbol table node of type
				SYM_VAR */
	sym_node_t*	node,	/* in: symbol table node allocated for the
				id of the variable */
	pars_res_word_t* type)	/* in: pointer to a type token */
{
	node->resolved = TRUE;
	node->token_type = SYM_VAR;

	node->param_type = PARS_NOT_PARAM;

	pars_set_dfield_type(que_node_get_val(node), type);
	
	return(node);
}

/*************************************************************************
Parses a procedure parameter declaration. */

sym_node_t*
pars_parameter_declaration(
/*=======================*/
				/* out, own: symbol table node of type
				SYM_VAR */
	sym_node_t*	node,	/* in: symbol table node allocated for the
				id of the parameter */
	ulint		param_type,
				/* in: PARS_INPUT or PARS_OUTPUT */
	pars_res_word_t* type)	/* in: pointer to a type token */
{	
	ut_a((param_type == PARS_INPUT) || (param_type == PARS_OUTPUT));

	pars_variable_declaration(node, type);

	node->param_type = param_type;

	return(node);
}

/*************************************************************************
Sets the parent field in a query node list. */
static
void
pars_set_parent_in_list(
/*====================*/
	que_node_t*	node_list,	/* in: first node in a list */
	que_node_t*	parent)		/* in: parent value to set in all
					nodes of the list */
{
	que_common_t*	common;

	common = node_list;

	while (common) {
		common->parent = parent;

		common = que_node_get_next(common);
	}
}	

/*************************************************************************
Parses an elsif element. */

elsif_node_t*
pars_elsif_element(
/*===============*/
					/* out: elsif node */
	que_node_t*	cond,		/* in: if-condition */
	que_node_t*	stat_list)	/* in: statement list */
{
	elsif_node_t*	node;

	node = mem_heap_alloc(pars_sym_tab_global->heap, sizeof(elsif_node_t));

	node->common.type = QUE_NODE_ELSIF;

	node->cond = cond;

	pars_resolve_exp_variables_and_types(NULL, cond);
	
	node->stat_list = stat_list;

	return(node);
}

/*************************************************************************
Parses an if-statement. */

if_node_t*
pars_if_statement(
/*==============*/
					/* out: if-statement node */
	que_node_t*	cond,		/* in: if-condition */
	que_node_t*	stat_list,	/* in: statement list */
	que_node_t*	else_part)	/* in: else-part statement list
					or elsif element list */
{
	if_node_t*	node;
	elsif_node_t*	elsif_node;

	node = mem_heap_alloc(pars_sym_tab_global->heap, sizeof(if_node_t));

	node->common.type = QUE_NODE_IF;