Enable multi-page temp tables

ChangeLog

@@ -1,5 +1,13 @@
 Wed Sep  8 22:24:29 CDT 2004	Jeff Smith <whydoubt@yahoo.com>
-	* HACKING: Small format documention correction
+	* HACKING: Small format documentation correction
+	* include/mdbtools.h:
+	* src/libmdb/data.c:
+	* src/libmdb/table.c:
+	* src/libmdb/worktable.c:
+	* src/libmdb/write.c:
+	* src/odbc/odbc.c:
+	* src/sql/mdbsql.c:
+	* src/util/mdb-sql.c: Enable multi-page temp tables
 
 Wed Sep  8 07:37:08 CDT 2004	Jeff Smith <whydoubt@yahoo.com>
 	* include/mdbtools.h:

include/mdbtools.h

@@ -346,6 +346,9 @@ typedef struct {
 	MdbIndexChain *chain;
 	MdbProperties	*props;
 	unsigned int num_var_cols;  /* to know if row has variable columns */
+	/* temp table */
+	unsigned int  is_temp_table;
+	GPtrArray     *temp_table_pages;
 } MdbTableDef;
 
 struct mdbindex {

src/libmdb/data.c

@@ -342,12 +342,26 @@ mdb_fetch_row(MdbTableDef *table)
 	if (!table->cur_pg_num) {
 		table->cur_pg_num=1;
 		table->cur_row=0;
-		if (table->strategy!=MDB_INDEX_SCAN) 
+		if ((!table->is_temp_table)&&(table->strategy!=MDB_INDEX_SCAN))
 			if (!mdb_read_next_dpg(table)) return 0;
 	}
 
 	do {
-		if (table->strategy==MDB_INDEX_SCAN) {
+		if (table->is_temp_table) {
+			GPtrArray *pages = table->temp_table_pages;
+			rows = mdb_get_int16(
+				g_ptr_array_index(pages, table->cur_pg_num-1),
+				fmt->row_count_offset);
+			if (table->cur_row >= rows) {
+				table->cur_row = 0;
+				table->cur_pg_num++;
+				if (table->cur_pg_num > pages->len)
+					return 0;
+			}
+			memcpy(mdb->pg_buf,
+				g_ptr_array_index(pages, table->cur_pg_num-1),
+				fmt->pg_size);
+		} else if (table->strategy==MDB_INDEX_SCAN) {
 		
 			if (!mdb_index_find_next(table->mdbidx, table->scan_idx, table->chain, &pg, (guint16 *) &(table->cur_row))) {
 				mdb_index_scan_free(table);

src/libmdb/table.c

@@ -56,6 +56,12 @@ MdbTableDef *mdb_alloc_tabledef(MdbCatalogEntry *entry)
 void mdb_free_tabledef(MdbTableDef *table)
 {
 	if (!table) return;
+	if (table->is_temp_table) {
+		unsigned int i;
+		for (i=0; i<table->temp_table_pages->len; i++)
+			g_free(g_ptr_array_index(table->temp_table_pages,i));
+		g_ptr_array_free(table->temp_table_pages, TRUE);
+	}
 	mdb_free_columns(table->columns);
 	mdb_free_indices(table->indices);
 	g_free(table->usage_map);

src/libmdb/worktable.c

@@ -62,6 +62,8 @@ mdb_create_temp_table(MdbHandle *mdb, char *name)
 
 	table = mdb_alloc_tabledef(entry);
 	table->columns = g_ptr_array_new();
+	table->is_temp_table = 1;
+	table->temp_table_pages = g_ptr_array_new();
 
 	return table;
 }

src/libmdb/write.c

@@ -449,14 +449,14 @@ mdb_pack_row(MdbTableDef *table, unsigned char *row_buffer, int unsigned num_fie
 int
 mdb_pg_get_freespace(MdbHandle *mdb)
 {
-MdbFormatConstants *fmt = mdb->fmt;
+	int rows, free_start, free_end;
-int rows, free_start, free_end;
+	int row_count_offset = mdb->fmt->row_count_offset;
 
-	rows = mdb_pg_get_int16(mdb, fmt->row_count_offset);
+	rows = mdb_pg_get_int16(mdb, row_count_offset);
-	free_start = fmt->row_count_offset + 2 + (rows * 2);
+	free_start = row_count_offset + 2 + (rows * 2);
-        free_end = mdb_pg_get_int16(mdb, (fmt->row_count_offset + rows * 2)) -1;
+        free_end = mdb_pg_get_int16(mdb, row_count_offset + (rows * 2));
 	mdb_debug(MDB_DEBUG_WRITE,"free space left on page = %d", free_end - free_start);
-	return (free_end - free_start + 1);
+	return (free_end - free_start);
 }
 unsigned char *
 mdb_new_leaf_pg(MdbCatalogEntry *entry)
@@ -475,13 +475,14 @@ mdb_new_leaf_pg(MdbCatalogEntry *entry)
 unsigned char *
 mdb_new_data_pg(MdbCatalogEntry *entry)
 {
-	MdbHandle *mdb = entry->mdb;
+	MdbFormatConstants *fmt = entry->mdb->fmt;
 	unsigned char *new_pg;
 
-	new_pg = (unsigned char *) g_malloc0(mdb->fmt->pg_size);
+	new_pg = (unsigned char *) g_malloc0(fmt->pg_size);
 		
 	new_pg[0]=0x01;
 	new_pg[1]=0x01;
+	_mdb_put_int16(new_pg, 2, fmt->pg_size - fmt->row_count_offset - 2);
 	_mdb_put_int32(new_pg, 4, entry->table_pg);
 	
 	return new_pg;
@@ -613,19 +614,37 @@ mdb_add_row_to_pg(MdbTableDef *table, unsigned char *row_buffer, int new_row_siz
 	MdbHandle *mdb = entry->mdb;
 	MdbFormatConstants *fmt = mdb->fmt;
 
-	new_pg = mdb_new_data_pg(entry);
+	if (table->is_temp_table) {
+		GPtrArray *pages = table->temp_table_pages;
+		if (pages->len == 0) {
+			new_pg = mdb_new_data_pg(entry);
+			g_ptr_array_add(pages, new_pg);
+		} else {
+			new_pg = g_ptr_array_index(pages, pages->len - 1);
+			if (mdb_get_int16(new_pg, 2) < new_row_size + 2) {
+				new_pg = mdb_new_data_pg(entry);
+				g_ptr_array_add(pages, new_pg);
+			}
+		}
 
-	num_rows = mdb_pg_get_int16(mdb, fmt->row_count_offset);
+		num_rows = mdb_get_int16(new_pg, fmt->row_count_offset);
-	pos = mdb->fmt->pg_size;
+		pos = (num_rows == 0) ? fmt->pg_size :
+			mdb_get_int16(new_pg, fmt->row_count_offset + (num_rows*2));
+	} else {  /* is not a temp table */
+		new_pg = mdb_new_data_pg(entry);
 
-	/* copy existing rows */
+		num_rows = mdb_pg_get_int16(mdb, fmt->row_count_offset);
-	for (i=0;i<num_rows;i++) {
+		pos = fmt->pg_size;
-		row_start = mdb_pg_get_int16(mdb, (fmt->row_count_offset + 2) + (i*2));
+
-		row_end = mdb_find_end_of_row(mdb, i);
+		/* copy existing rows */
-		row_size = row_end - row_start + 1;
+		for (i=0;i<num_rows;i++) {
-		pos -= row_size;
+			row_start = mdb_pg_get_int16(mdb, (fmt->row_count_offset + 2) + (i*2));
-		memcpy(&new_pg[pos], &mdb->pg_buf[row_start], row_size);
+			row_end = mdb_find_end_of_row(mdb, i);
-		_mdb_put_int16(new_pg, (fmt->row_count_offset + 2) + (i*2), pos);
+			row_size = row_end - row_start + 1;
+			pos -= row_size;
+			memcpy(&new_pg[pos], &mdb->pg_buf[row_start], row_size);
+			_mdb_put_int16(new_pg, (fmt->row_count_offset + 2) + (i*2), pos);
+		}
 	}
 
 	/* add our new row */
@@ -638,12 +657,14 @@ mdb_add_row_to_pg(MdbTableDef *table, unsigned char *row_buffer, int new_row_siz
 	num_rows++;
 	_mdb_put_int16(new_pg, fmt->row_count_offset, num_rows);
 
-	/* copy new page over old */
-	memcpy(mdb->pg_buf, new_pg, fmt->pg_size);
-	g_free(new_pg);
-
 	/* update the freespace */
-	_mdb_put_int16(mdb->pg_buf, 2, mdb_pg_get_freespace(mdb));
+	_mdb_put_int16(new_pg,2,pos - fmt->row_count_offset - 2 - (num_rows*2));
+
+	/* copy new page over old */
+	if (!table->is_temp_table) {
+		memcpy(mdb->pg_buf, new_pg, fmt->pg_size);
+		g_free(new_pg);
+	}
 
 	return num_rows;
 }

src/odbc/odbc.c

@@ -32,7 +32,7 @@
 
 #include "connectparams.h"
 
-static char  software_version[]   = "$Id: odbc.c,v 1.18 2004/05/30 08:06:43 whydoubt Exp $";
+static char  software_version[]   = "$Id: odbc.c,v 1.19 2004/09/09 03:44:36 whydoubt Exp $";
 static void *no_unused_var_warn[] = {software_version,
                                      no_unused_var_warn};
 
@@ -851,7 +851,7 @@ struct _henv *env = (struct _henv *) dbc->henv;
         //cur = cur->next;
 	//}
 
-	if (mdb_sql_fetch_row(env->sql, env->sql->cur_table)) {
+	if (mdb_fetch_row(env->sql->cur_table)) {
 		stmt->rows_affected++;
 		return SQL_SUCCESS;
 	} else {
@@ -1293,11 +1293,6 @@ SQLRETURN SQL_API SQLGetTypeInfo(
 	mdb_sql_add_temp_col(sql, ttable, 17, "NUM_PREC_RADIX", MDB_INT, 0, 1);
 	mdb_sql_add_temp_col(sql, ttable, 18, "INTERVAL_PRECISION", MDB_INT, 0, 1);
 
-	/* blank out the pg_buf */
-	new_pg = mdb_new_data_pg(ttable->entry);
-	memcpy(mdb->pg_buf, new_pg, mdb->fmt->pg_size);
-	g_free(new_pg);
-
 	for (i=0; i<MAX_TYPE_INFO; i++) {
 		if (!fSqlType || fSqlType == type_info[i].data_type) {
 			tmpsiz = mdb_ascii2unicode(mdb, type_info[i].type_name, 0, 100, tmpstr);
@@ -1330,7 +1325,6 @@ SQLRETURN SQL_API SQLGetTypeInfo(
 			ttable->num_rows++;
 		}
 	}
-	sql->kludge_ttable_pg = g_memdup(mdb->pg_buf, mdb->fmt->pg_size);
 	sql->cur_table = ttable;
 	
 	/* return _SQLExecute(hstmt); */

src/sql/mdbsql.c

@@ -436,11 +436,6 @@ void mdb_sql_reset(MdbSQL *sql)
 		sql->cur_table = NULL;
 	}
 
-	if (sql->kludge_ttable_pg) {
-		g_free(sql->kludge_ttable_pg);
-		sql->kludge_ttable_pg = NULL;
-	}
-
 	/* Reset columns */
 	g_ptr_array_foreach(sql->columns, mdb_sql_free_column, NULL);
 	g_ptr_array_free(sql->columns, TRUE);
@@ -511,11 +506,6 @@ void mdb_sql_listtables(MdbSQL *sql)
 	ttable = mdb_create_temp_table(mdb, "#listtables");
 	mdb_sql_add_temp_col(sql, ttable, 0, "Tables", MDB_TEXT, 30, 0);
 
-	/* blank out the pg_buf */
-	new_pg = mdb_new_data_pg(ttable->entry);
-	memcpy(mdb->pg_buf, new_pg, mdb->fmt->pg_size);
-	g_free(new_pg);
-
  	/* loop over each entry in the catalog */
  	for (i=0; i < mdb->num_catalog; i++) {
      		entry = g_ptr_array_index (mdb->catalog, i);
@@ -530,7 +520,6 @@ void mdb_sql_listtables(MdbSQL *sql)
 			ttable->num_rows++;
 		}
 	}
-	sql->kludge_ttable_pg = g_memdup(mdb->pg_buf, mdb->fmt->pg_size);
 	sql->cur_table = ttable;
 
 }
@@ -586,11 +575,6 @@ void mdb_sql_describe_table(MdbSQL *sql)
 	mdb_sql_add_temp_col(sql, ttable, 1, "Type", MDB_TEXT, 20, 0);
 	mdb_sql_add_temp_col(sql, ttable, 2, "Size", MDB_TEXT, 10, 0);
 
-	/* blank out the pg_buf */
-	new_pg = mdb_new_data_pg(ttable->entry);
-	memcpy(mdb->pg_buf, new_pg, mdb->fmt->pg_size);
-	g_free(new_pg);
-
      for (i=0;i<table->num_cols;i++) {
 
         col = g_ptr_array_index(table->columns,i);
@@ -612,7 +596,6 @@ void mdb_sql_describe_table(MdbSQL *sql)
 
 	/* the column and table names are no good now */
 	//mdb_sql_reset(sql);
-	sql->kludge_ttable_pg = g_memdup(mdb->pg_buf, mdb->fmt->pg_size);
 	sql->cur_table = ttable;
 }
 
@@ -755,28 +738,13 @@ mdb_sql_bind_all(MdbSQL *sql)
 	}
 }
 /*
- * mdb_sql_fetch_row should be called instead of mdb_fetch_row when there may be 
+ * mdb_sql_fetch_row is now just a wrapper around mdb_fetch_row.
- * work tables involved (currently implemented as kludge_ttable_pg)
+ *   It is left here only for backward compatibility.
  */
 int
 mdb_sql_fetch_row(MdbSQL *sql, MdbTableDef *table)
 {
-	MdbHandle *mdb = table->entry->mdb;
+	return mdb_fetch_row(table);
-	MdbFormatConstants *fmt = mdb->fmt;
-	unsigned int rows;
-
-        if (sql->kludge_ttable_pg) {
-                memcpy(mdb->pg_buf, sql->kludge_ttable_pg, fmt->pg_size);
-
-		rows = mdb_pg_get_int16(mdb,fmt->row_count_offset);
-		if (rows > table->cur_row) {
-			mdb_read_row(sql->cur_table, table->cur_row++);
-			return 1;
-		}
-		return 0;
-	} else {
-		return mdb_fetch_row(table);
-	}
 }
 
 void 

src/util/mdb-sql.c

@@ -321,21 +321,7 @@ dump_results_pp(MdbSQL *sql)
 	fprintf(stdout,"\n");
 
 	/* print each row */
-	/*
+	while(mdb_fetch_row(sql->cur_table)) {
-	if (sql->kludge_ttable_pg) {
-		memcpy(mdb->pg_buf, sql->kludge_ttable_pg, fmt->pg_size);
-		rows = mdb_pg_get_int16(mdb,fmt->row_count_offset);
-	for (i = 0; i < rows; i++) {
-		rc = mdb_read_row(sql->cur_table, i);
-		row_count++;
-  		for (j=0;j<sql->num_columns;j++) {
-			sqlcol = g_ptr_array_index(sql->columns,j);
-			print_value(sql->bound_values[j],sqlcol->disp_size,!j);
-		}
-		fprintf(stdout,"\n");
-	}
-	*/
-	while(mdb_sql_fetch_row(sql, sql->cur_table)) {
 		row_count++;
   		for (j=0;j<sql->num_columns;j++) {
 			sqlcol = g_ptr_array_index(sql->columns,j);