** algorithms packaged as an SQLite virtual table module.
*/
+/*
+** Database Format of R-Tree Tables
+** --------------------------------
+**
+** The data structure for a single virtual r-tree table is stored in three
+** native SQLite tables declared as follows. In each case, the '%' character
+** in the table name is replaced with the user-supplied name of the r-tree
+** table.
+**
+** CREATE TABLE %_node(nodeno INTEGER PRIMARY KEY, data BLOB)
+** CREATE TABLE %_parent(nodeno INTEGER PRIMARY KEY, parentnode INTEGER)
+** CREATE TABLE %_rowid(rowid INTEGER PRIMARY KEY, nodeno INTEGER)
+**
+** The data for each node of the r-tree structure is stored in the %_node
+** table. For each node that is not the root node of the r-tree, there is
+** an entry in the %_parent table associating the node with its parent.
+** And for each row of data in the table, there is an entry in the %_rowid
+** table that maps from the entries rowid to the id of the node that it
+** is stored on.
+**
+** The root node of an r-tree always exists, even if the r-tree table is
+** empty. The nodeno of the root node is always 1. All other nodes in the
+** table must be the same size as the root node. The content of each node
+** is formatted as follows:
+**
+** 1. If the node is the root node (node 1), then the first 2 bytes
+** of the node contain the tree depth as a big-endian integer.
+** For non-root nodes, the first 2 bytes are left unused.
+**
+** 2. The next 2 bytes contain the number of entries currently
+** stored in the node.
+**
+** 3. The remainder of the node contains the node entries. Each entry
+** consists of a single 8-byte integer followed by an even number
+** of 4-byte coordinates. For leaf nodes the integer is the rowid
+** of a record. For internal nodes it is the node number of a
+** child page.
+*/
+
#if !defined(SQLITE_CORE) || defined(SQLITE_ENABLE_RTREE)
/*
#define AssignCells splitNodeStartree
#endif
+#if !defined(NDEBUG) && !defined(SQLITE_DEBUG)
+# define NDEBUG 1
+#endif
#ifndef SQLITE_CORE
#include "sqlite3ext.h"
#include <assert.h>
#ifndef SQLITE_AMALGAMATION
+#include "sqlite3rtree.h"
typedef sqlite3_int64 i64;
typedef unsigned char u8;
typedef unsigned int u32;
typedef struct RtreeNode RtreeNode;
typedef struct RtreeCell RtreeCell;
typedef struct RtreeConstraint RtreeConstraint;
+typedef struct RtreeMatchArg RtreeMatchArg;
+typedef struct RtreeGeomCallback RtreeGeomCallback;
typedef union RtreeCoord RtreeCoord;
/* The rtree may have between 1 and RTREE_MAX_DIMENSIONS dimensions. */
#define RTREE_REINSERT(p) RTREE_MINCELLS(p)
#define RTREE_MAXCELLS 51
+/*
+** The smallest possible node-size is (512-64)==448 bytes. And the largest
+** supported cell size is 48 bytes (8 byte rowid + ten 4 byte coordinates).
+** Therefore all non-root nodes must contain at least 3 entries. Since
+** 2^40 is greater than 2^64, an r-tree structure always has a depth of
+** 40 or less.
+*/
+#define RTREE_MAX_DEPTH 40
+
/*
** An rtree cursor object.
*/
** A search constraint.
*/
struct RtreeConstraint {
- int iCoord; /* Index of constrained coordinate */
- int op; /* Constraining operation */
- double rValue; /* Constraint value. */
+ int iCoord; /* Index of constrained coordinate */
+ int op; /* Constraining operation */
+ double rValue; /* Constraint value. */
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+ sqlite3_rtree_geometry *pGeom; /* Constraint callback argument for a MATCH */
};
/* Possible values for RtreeConstraint.op */
-#define RTREE_EQ 0x41
-#define RTREE_LE 0x42
-#define RTREE_LT 0x43
-#define RTREE_GE 0x44
-#define RTREE_GT 0x45
+#define RTREE_EQ 0x41
+#define RTREE_LE 0x42
+#define RTREE_LT 0x43
+#define RTREE_GE 0x44
+#define RTREE_GT 0x45
+#define RTREE_MATCH 0x46
/*
** An rtree structure node.
-**
-** Data format (RtreeNode.zData):
-**
-** 1. If the node is the root node (node 1), then the first 2 bytes
-** of the node contain the tree depth as a big-endian integer.
-** For non-root nodes, the first 2 bytes are left unused.
-**
-** 2. The next 2 bytes contain the number of entries currently
-** stored in the node.
-**
-** 3. The remainder of the node contains the node entries. Each entry
-** consists of a single 8-byte integer followed by an even number
-** of 4-byte coordinates. For leaf nodes the integer is the rowid
-** of a record. For internal nodes it is the node number of a
-** child page.
*/
struct RtreeNode {
RtreeNode *pParent; /* Parent node */
RtreeCoord aCoord[RTREE_MAX_DIMENSIONS*2];
};
+
+/*
+** Value for the first field of every RtreeMatchArg object. The MATCH
+** operator tests that the first field of a blob operand matches this
+** value to avoid operating on invalid blobs (which could cause a segfault).
+*/
+#define RTREE_GEOMETRY_MAGIC 0x891245AB
+
+/*
+** An instance of this structure must be supplied as a blob argument to
+** the right-hand-side of an SQL MATCH operator used to constrain an
+** r-tree query.
+*/
+struct RtreeMatchArg {
+ u32 magic; /* Always RTREE_GEOMETRY_MAGIC */
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+ void *pContext;
+ int nParam;
+ double aParam[1];
+};
+
+/*
+** When a geometry callback is created (see sqlite3_rtree_geometry_callback),
+** a single instance of the following structure is allocated. It is used
+** as the context for the user-function created by by s_r_g_c(). The object
+** is eventually deleted by the destructor mechanism provided by
+** sqlite3_create_function_v2() (which is called by s_r_g_c() to create
+** the geometry callback function).
+*/
+struct RtreeGeomCallback {
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *);
+ void *pContext;
+};
+
#ifndef MAX
# define MAX(x,y) ((x) < (y) ? (y) : (x))
#endif
** Clear the content of node p (set all bytes to 0x00).
*/
static void nodeZero(Rtree *pRtree, RtreeNode *p){
- if( p ){
- memset(&p->zData[2], 0, pRtree->iNodeSize-2);
- p->isDirty = 1;
- }
+ memset(&p->zData[2], 0, pRtree->iNodeSize-2);
+ p->isDirty = 1;
}
/*
*/
static RtreeNode *nodeHashLookup(Rtree *pRtree, i64 iNode){
RtreeNode *p;
- assert( iNode!=0 );
for(p=pRtree->aHash[nodeHash(iNode)]; p && p->iNode!=iNode; p=p->pNext);
return p;
}
** Add node pNode to the node hash table.
*/
static void nodeHashInsert(Rtree *pRtree, RtreeNode *pNode){
- if( pNode ){
- int iHash;
- assert( pNode->pNext==0 );
- iHash = nodeHash(pNode->iNode);
- pNode->pNext = pRtree->aHash[iHash];
- pRtree->aHash[iHash] = pNode;
- }
+ int iHash;
+ assert( pNode->pNext==0 );
+ iHash = nodeHash(pNode->iNode);
+ pNode->pNext = pRtree->aHash[iHash];
+ pRtree->aHash[iHash] = pNode;
}
/*
** assigned a node number when nodeWrite() is called to write the
** node contents out to the database.
*/
-static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent, int zero){
+static RtreeNode *nodeNew(Rtree *pRtree, RtreeNode *pParent){
RtreeNode *pNode;
pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
if( pNode ){
- memset(pNode, 0, sizeof(RtreeNode) + (zero?pRtree->iNodeSize:0));
+ memset(pNode, 0, sizeof(RtreeNode) + pRtree->iNodeSize);
pNode->zData = (u8 *)&pNode[1];
pNode->nRef = 1;
pNode->pParent = pParent;
RtreeNode **ppNode /* OUT: Acquired node */
){
int rc;
+ int rc2 = SQLITE_OK;
RtreeNode *pNode;
/* Check if the requested node is already in the hash table. If so,
return SQLITE_OK;
}
- pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode) + pRtree->iNodeSize);
- if( !pNode ){
- *ppNode = 0;
- return SQLITE_NOMEM;
- }
- pNode->pParent = pParent;
- pNode->zData = (u8 *)&pNode[1];
- pNode->nRef = 1;
- pNode->iNode = iNode;
- pNode->isDirty = 0;
- pNode->pNext = 0;
-
sqlite3_bind_int64(pRtree->pReadNode, 1, iNode);
rc = sqlite3_step(pRtree->pReadNode);
if( rc==SQLITE_ROW ){
const u8 *zBlob = sqlite3_column_blob(pRtree->pReadNode, 0);
- assert( sqlite3_column_bytes(pRtree->pReadNode, 0)==pRtree->iNodeSize );
- memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
- nodeReference(pParent);
- }else{
- sqlite3_free(pNode);
- pNode = 0;
+ if( pRtree->iNodeSize==sqlite3_column_bytes(pRtree->pReadNode, 0) ){
+ pNode = (RtreeNode *)sqlite3_malloc(sizeof(RtreeNode)+pRtree->iNodeSize);
+ if( !pNode ){
+ rc2 = SQLITE_NOMEM;
+ }else{
+ pNode->pParent = pParent;
+ pNode->zData = (u8 *)&pNode[1];
+ pNode->nRef = 1;
+ pNode->iNode = iNode;
+ pNode->isDirty = 0;
+ pNode->pNext = 0;
+ memcpy(pNode->zData, zBlob, pRtree->iNodeSize);
+ nodeReference(pParent);
+ }
+ }
}
-
- *ppNode = pNode;
rc = sqlite3_reset(pRtree->pReadNode);
+ if( rc==SQLITE_OK ) rc = rc2;
- if( rc==SQLITE_OK && iNode==1 ){
+ /* If the root node was just loaded, set pRtree->iDepth to the height
+ ** of the r-tree structure. A height of zero means all data is stored on
+ ** the root node. A height of one means the children of the root node
+ ** are the leaves, and so on. If the depth as specified on the root node
+ ** is greater than RTREE_MAX_DEPTH, the r-tree structure must be corrupt.
+ */
+ if( pNode && iNode==1 ){
pRtree->iDepth = readInt16(pNode->zData);
+ if( pRtree->iDepth>RTREE_MAX_DEPTH ){
+ rc = SQLITE_CORRUPT;
+ }
}
- if( pNode!=0 ){
- nodeHashInsert(pRtree, pNode);
- }else if( rc==SQLITE_OK ){
- rc = SQLITE_CORRUPT;
+ /* If no error has occurred so far, check if the "number of entries"
+ ** field on the node is too large. If so, set the return code to
+ ** SQLITE_CORRUPT.
+ */
+ if( pNode && rc==SQLITE_OK ){
+ if( NCELL(pNode)>((pRtree->iNodeSize-4)/pRtree->nBytesPerCell) ){
+ rc = SQLITE_CORRUPT;
+ }
+ }
+
+ if( rc==SQLITE_OK ){
+ if( pNode!=0 ){
+ nodeHashInsert(pRtree, pNode);
+ }else{
+ rc = SQLITE_CORRUPT;
+ }
+ *ppNode = pNode;
+ }else{
+ sqlite3_free(pNode);
+ *ppNode = 0;
}
return rc;
nMaxCell = (pRtree->iNodeSize-4)/pRtree->nBytesPerCell;
nCell = NCELL(pNode);
- assert(nCell<=nMaxCell);
-
+ assert( nCell<=nMaxCell );
if( nCell<nMaxCell ){
nodeOverwriteCell(pRtree, pNode, pCell, nCell);
writeInt16(&pNode->zData[2], nCell+1);
return rc;
}
+
+/*
+** Free the RtreeCursor.aConstraint[] array and its contents.
+*/
+static void freeCursorConstraints(RtreeCursor *pCsr){
+ if( pCsr->aConstraint ){
+ int i; /* Used to iterate through constraint array */
+ for(i=0; i<pCsr->nConstraint; i++){
+ sqlite3_rtree_geometry *pGeom = pCsr->aConstraint[i].pGeom;
+ if( pGeom ){
+ if( pGeom->xDelUser ) pGeom->xDelUser(pGeom->pUser);
+ sqlite3_free(pGeom);
+ }
+ }
+ sqlite3_free(pCsr->aConstraint);
+ pCsr->aConstraint = 0;
+ }
+}
+
/*
** Rtree virtual table module xClose method.
*/
Rtree *pRtree = (Rtree *)(cur->pVtab);
int rc;
RtreeCursor *pCsr = (RtreeCursor *)cur;
- sqlite3_free(pCsr->aConstraint);
+ freeCursorConstraints(pCsr);
rc = nodeRelease(pRtree, pCsr->pNode);
sqlite3_free(pCsr);
return rc;
return (pCsr->pNode==0);
}
+/*
+** The r-tree constraint passed as the second argument to this function is
+** guaranteed to be a MATCH constraint.
+*/
+static int testRtreeGeom(
+ Rtree *pRtree, /* R-Tree object */
+ RtreeConstraint *pConstraint, /* MATCH constraint to test */
+ RtreeCell *pCell, /* Cell to test */
+ int *pbRes /* OUT: Test result */
+){
+ int i;
+ double aCoord[RTREE_MAX_DIMENSIONS*2];
+ int nCoord = pRtree->nDim*2;
+
+ assert( pConstraint->op==RTREE_MATCH );
+ assert( pConstraint->pGeom );
+
+ for(i=0; i<nCoord; i++){
+ aCoord[i] = DCOORD(pCell->aCoord[i]);
+ }
+ return pConstraint->xGeom(pConstraint->pGeom, nCoord, aCoord, pbRes);
+}
+
/*
** Cursor pCursor currently points to a cell in a non-leaf page.
-** Return true if the sub-tree headed by the cell is filtered
+** Set *pbEof to true if the sub-tree headed by the cell is filtered
** (excluded) by the constraints in the pCursor->aConstraint[]
** array, or false otherwise.
+**
+** Return SQLITE_OK if successful or an SQLite error code if an error
+** occurs within a geometry callback.
*/
-static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor){
+static int testRtreeCell(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){
RtreeCell cell;
int ii;
int bRes = 0;
double cell_max = DCOORD(cell.aCoord[(p->iCoord>>1)*2+1]);
assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE
- || p->op==RTREE_GT || p->op==RTREE_EQ
+ || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH
);
switch( p->op ){
- case RTREE_LE: case RTREE_LT: bRes = p->rValue<cell_min; break;
- case RTREE_GE: case RTREE_GT: bRes = p->rValue>cell_max; break;
- case RTREE_EQ:
+ case RTREE_LE: case RTREE_LT:
+ bRes = p->rValue<cell_min;
+ break;
+
+ case RTREE_GE: case RTREE_GT:
+ bRes = p->rValue>cell_max;
+ break;
+
+ case RTREE_EQ:
bRes = (p->rValue>cell_max || p->rValue<cell_min);
break;
+
+ default: {
+ int rc;
+ assert( p->op==RTREE_MATCH );
+ rc = testRtreeGeom(pRtree, p, &cell, &bRes);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ bRes = !bRes;
+ break;
+ }
}
}
- return bRes;
+ *pbEof = bRes;
+ return SQLITE_OK;
}
/*
-** Return true if the cell that cursor pCursor currently points to
+** Test if the cell that cursor pCursor currently points to
** would be filtered (excluded) by the constraints in the
-** pCursor->aConstraint[] array, or false otherwise.
+** pCursor->aConstraint[] array. If so, set *pbEof to true before
+** returning. If the cell is not filtered (excluded) by the constraints,
+** set pbEof to zero.
+**
+** Return SQLITE_OK if successful or an SQLite error code if an error
+** occurs within a geometry callback.
**
** This function assumes that the cell is part of a leaf node.
*/
-static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor){
+static int testRtreeEntry(Rtree *pRtree, RtreeCursor *pCursor, int *pbEof){
RtreeCell cell;
int ii;
+ *pbEof = 0;
nodeGetCell(pRtree, pCursor->pNode, pCursor->iCell, &cell);
for(ii=0; ii<pCursor->nConstraint; ii++){
double coord = DCOORD(cell.aCoord[p->iCoord]);
int res;
assert(p->op==RTREE_LE || p->op==RTREE_LT || p->op==RTREE_GE
- || p->op==RTREE_GT || p->op==RTREE_EQ
+ || p->op==RTREE_GT || p->op==RTREE_EQ || p->op==RTREE_MATCH
);
switch( p->op ){
case RTREE_LE: res = (coord<=p->rValue); break;
case RTREE_GE: res = (coord>=p->rValue); break;
case RTREE_GT: res = (coord>p->rValue); break;
case RTREE_EQ: res = (coord==p->rValue); break;
+ default: {
+ int rc;
+ assert( p->op==RTREE_MATCH );
+ rc = testRtreeGeom(pRtree, p, &cell, &res);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
+ break;
+ }
}
- if( !res ) return 1;
+ if( !res ){
+ *pbEof = 1;
+ return SQLITE_OK;
+ }
}
- return 0;
+ return SQLITE_OK;
}
/*
assert( iHeight>=0 );
if( iHeight==0 ){
- isEof = testRtreeEntry(pRtree, pCursor);
+ rc = testRtreeEntry(pRtree, pCursor, &isEof);
}else{
- isEof = testRtreeCell(pRtree, pCursor);
+ rc = testRtreeCell(pRtree, pCursor, &isEof);
}
- if( isEof || iHeight==0 ){
+ if( rc!=SQLITE_OK || isEof || iHeight==0 ){
*pEof = isEof;
- return SQLITE_OK;
+ return rc;
}
iRowid = nodeGetRowid(pRtree, pCursor->pNode, pCursor->iCell);
** One of the cells in node pNode is guaranteed to have a 64-bit
** integer value equal to iRowid. Return the index of this cell.
*/
-static int nodeRowidIndex(Rtree *pRtree, RtreeNode *pNode, i64 iRowid){
+static int nodeRowidIndex(
+ Rtree *pRtree,
+ RtreeNode *pNode,
+ i64 iRowid,
+ int *piIndex
+){
int ii;
- for(ii=0; nodeGetRowid(pRtree, pNode, ii)!=iRowid; ii++){
- assert( ii<(NCELL(pNode)-1) );
+ int nCell = NCELL(pNode);
+ for(ii=0; ii<nCell; ii++){
+ if( nodeGetRowid(pRtree, pNode, ii)==iRowid ){
+ *piIndex = ii;
+ return SQLITE_OK;
+ }
}
- return ii;
+ return SQLITE_CORRUPT;
}
/*
** Return the index of the cell containing a pointer to node pNode
** in its parent. If pNode is the root node, return -1.
*/
-static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode){
+static int nodeParentIndex(Rtree *pRtree, RtreeNode *pNode, int *piIndex){
RtreeNode *pParent = pNode->pParent;
if( pParent ){
- return nodeRowidIndex(pRtree, pParent, pNode->iNode);
+ return nodeRowidIndex(pRtree, pParent, pNode->iNode, piIndex);
}
- return -1;
+ *piIndex = -1;
+ return SQLITE_OK;
}
/*
RtreeCursor *pCsr = (RtreeCursor *)pVtabCursor;
int rc = SQLITE_OK;
+ /* RtreeCursor.pNode must not be NULL. If is is NULL, then this cursor is
+ ** already at EOF. It is against the rules to call the xNext() method of
+ ** a cursor that has already reached EOF.
+ */
+ assert( pCsr->pNode );
+
if( pCsr->iStrategy==1 ){
/* This "scan" is a direct lookup by rowid. There is no next entry. */
nodeRelease(pRtree, pCsr->pNode);
pCsr->pNode = 0;
- }
-
- else if( pCsr->pNode ){
+ }else{
/* Move to the next entry that matches the configured constraints. */
int iHeight = 0;
while( pCsr->pNode ){
}
}
pCsr->pNode = pNode->pParent;
- pCsr->iCell = nodeParentIndex(pRtree, pNode);
+ rc = nodeParentIndex(pRtree, pNode, &pCsr->iCell);
+ if( rc!=SQLITE_OK ){
+ return rc;
+ }
nodeReference(pCsr->pNode);
nodeRelease(pRtree, pNode);
iHeight++;
return rc;
}
+/*
+** This function is called to configure the RtreeConstraint object passed
+** as the second argument for a MATCH constraint. The value passed as the
+** first argument to this function is the right-hand operand to the MATCH
+** operator.
+*/
+static int deserializeGeometry(sqlite3_value *pValue, RtreeConstraint *pCons){
+ RtreeMatchArg *p;
+ sqlite3_rtree_geometry *pGeom;
+ int nBlob;
+
+ /* Check that value is actually a blob. */
+ if( !sqlite3_value_type(pValue)==SQLITE_BLOB ) return SQLITE_ERROR;
+
+ /* Check that the blob is roughly the right size. */
+ nBlob = sqlite3_value_bytes(pValue);
+ if( nBlob<sizeof(RtreeMatchArg)
+ || ((nBlob-sizeof(RtreeMatchArg))%sizeof(double))!=0
+ ){
+ return SQLITE_ERROR;
+ }
+
+ pGeom = (sqlite3_rtree_geometry *)sqlite3_malloc(
+ sizeof(sqlite3_rtree_geometry) + nBlob
+ );
+ if( !pGeom ) return SQLITE_NOMEM;
+ memset(pGeom, 0, sizeof(sqlite3_rtree_geometry));
+ p = (RtreeMatchArg *)&pGeom[1];
+
+ memcpy(p, sqlite3_value_blob(pValue), nBlob);
+ if( p->magic!=RTREE_GEOMETRY_MAGIC
+ || nBlob!=(sizeof(RtreeMatchArg) + (p->nParam-1)*sizeof(double))
+ ){
+ sqlite3_free(pGeom);
+ return SQLITE_ERROR;
+ }
+
+ pGeom->pContext = p->pContext;
+ pGeom->nParam = p->nParam;
+ pGeom->aParam = p->aParam;
+
+ pCons->xGeom = p->xGeom;
+ pCons->pGeom = pGeom;
+ return SQLITE_OK;
+}
/*
** Rtree virtual table module xFilter method.
rtreeReference(pRtree);
- sqlite3_free(pCsr->aConstraint);
- pCsr->aConstraint = 0;
+ freeCursorConstraints(pCsr);
pCsr->iStrategy = idxNum;
if( idxNum==1 ){
i64 iRowid = sqlite3_value_int64(argv[0]);
rc = findLeafNode(pRtree, iRowid, &pLeaf);
pCsr->pNode = pLeaf;
- if( pLeaf && rc==SQLITE_OK ){
- pCsr->iCell = nodeRowidIndex(pRtree, pLeaf, iRowid);
+ if( pLeaf ){
+ assert( rc==SQLITE_OK );
+ rc = nodeRowidIndex(pRtree, pLeaf, iRowid, &pCsr->iCell);
}
}else{
/* Normal case - r-tree scan. Set up the RtreeCursor.aConstraint array
if( !pCsr->aConstraint ){
rc = SQLITE_NOMEM;
}else{
+ memset(pCsr->aConstraint, 0, sizeof(RtreeConstraint)*argc);
assert( (idxStr==0 && argc==0) || strlen(idxStr)==argc*2 );
for(ii=0; ii<argc; ii++){
RtreeConstraint *p = &pCsr->aConstraint[ii];
p->op = idxStr[ii*2];
p->iCoord = idxStr[ii*2+1]-'a';
- p->rValue = sqlite3_value_double(argv[ii]);
+ if( p->op==RTREE_MATCH ){
+ /* A MATCH operator. The right-hand-side must be a blob that
+ ** can be cast into an RtreeMatchArg object. One created using
+ ** an sqlite3_rtree_geometry_callback() SQL user function.
+ */
+ rc = deserializeGeometry(argv[ii], p);
+ if( rc!=SQLITE_OK ){
+ break;
+ }
+ }else{
+ p->rValue = sqlite3_value_double(argv[ii]);
+ }
}
}
}
** idxNum idxStr Strategy
** ------------------------------------------------
** 1 Unused Direct lookup by rowid.
-** 2 See below R-tree query.
-** 3 Unused Full table scan.
+** 2 See below R-tree query or full-table scan.
** ------------------------------------------------
**
-** If strategy 1 or 3 is used, then idxStr is not meaningful. If strategy
+** If strategy 1 is used, then idxStr is not meaningful. If strategy
** 2 is used, idxStr is formatted to contain 2 bytes for each
** constraint used. The first two bytes of idxStr correspond to
** the constraint in sqlite3_index_info.aConstraintUsage[] with
** < 0x43 ('C')
** >= 0x44 ('D')
** > 0x45 ('E')
+** MATCH 0x46 ('F')
** ----------------------
**
** The second of each pair of bytes identifies the coordinate column
return SQLITE_OK;
}
- if( p->usable && p->iColumn>0 ){
+ if( p->usable && (p->iColumn>0 || p->op==SQLITE_INDEX_CONSTRAINT_MATCH) ){
+ int j, opmsk;
+ static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
u8 op = 0;
switch( p->op ){
case SQLITE_INDEX_CONSTRAINT_EQ: op = RTREE_EQ; break;
case SQLITE_INDEX_CONSTRAINT_LE: op = RTREE_LE; break;
case SQLITE_INDEX_CONSTRAINT_LT: op = RTREE_LT; break;
case SQLITE_INDEX_CONSTRAINT_GE: op = RTREE_GE; break;
+ default:
+ assert( p->op==SQLITE_INDEX_CONSTRAINT_MATCH );
+ op = RTREE_MATCH;
+ break;
}
- if( op ){
- /* Make sure this particular constraint has not been used before.
- ** If it has been used before, ignore it.
- **
- ** A <= or < can be used if there is a prior >= or >.
- ** A >= or > can be used if there is a prior < or <=.
- ** A <= or < is disqualified if there is a prior <=, <, or ==.
- ** A >= or > is disqualified if there is a prior >=, >, or ==.
- ** A == is disqualifed if there is any prior constraint.
- */
- int j, opmsk;
- static const unsigned char compatible[] = { 0, 0, 1, 1, 2, 2 };
- assert( compatible[RTREE_EQ & 7]==0 );
- assert( compatible[RTREE_LT & 7]==1 );
- assert( compatible[RTREE_LE & 7]==1 );
- assert( compatible[RTREE_GT & 7]==2 );
- assert( compatible[RTREE_GE & 7]==2 );
- cCol = p->iColumn - 1 + 'a';
- opmsk = compatible[op & 7];
- for(j=0; j<iIdx; j+=2){
- if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
- op = 0;
- break;
- }
+ assert( op!=0 );
+
+ /* Make sure this particular constraint has not been used before.
+ ** If it has been used before, ignore it.
+ **
+ ** A <= or < can be used if there is a prior >= or >.
+ ** A >= or > can be used if there is a prior < or <=.
+ ** A <= or < is disqualified if there is a prior <=, <, or ==.
+ ** A >= or > is disqualified if there is a prior >=, >, or ==.
+ ** A == is disqualifed if there is any prior constraint.
+ */
+ assert( compatible[RTREE_EQ & 7]==0 );
+ assert( compatible[RTREE_LT & 7]==1 );
+ assert( compatible[RTREE_LE & 7]==1 );
+ assert( compatible[RTREE_GT & 7]==2 );
+ assert( compatible[RTREE_GE & 7]==2 );
+ cCol = p->iColumn - 1 + 'a';
+ opmsk = compatible[op & 7];
+ for(j=0; j<iIdx; j+=2){
+ if( zIdxStr[j+1]==cCol && (compatible[zIdxStr[j] & 7] & opmsk)!=0 ){
+ op = 0;
+ break;
}
}
if( op ){
int ii;
float overlap = 0.0;
for(ii=0; ii<nCell; ii++){
- if( ii!=iExclude ){
+#if VARIANT_RSTARTREE_CHOOSESUBTREE
+ if( ii!=iExclude )
+#else
+ assert( iExclude==-1 );
+#endif
+ {
int jj;
float o = 1.0;
for(jj=0; jj<(pRtree->nDim*2); jj+=2){
** the smallest area.
*/
for(iCell=0; iCell<nCell; iCell++){
+ int bBest = 0;
float growth;
float area;
float overlap = 0.0;
nodeGetCell(pRtree, pNode, iCell, &cell);
growth = cellGrowth(pRtree, &cell, pCell);
area = cellArea(pRtree, &cell);
+
#if VARIANT_RSTARTREE_CHOOSESUBTREE
if( ii==(pRtree->iDepth-1) ){
overlap = cellOverlapEnlargement(pRtree,&cell,pCell,aCell,nCell,iCell);
}
-#endif
if( (iCell==0)
|| (overlap<fMinOverlap)
|| (overlap==fMinOverlap && growth<fMinGrowth)
|| (overlap==fMinOverlap && growth==fMinGrowth && area<fMinArea)
){
+ bBest = 1;
+ }
+#else
+ if( iCell==0||growth<fMinGrowth||(growth==fMinGrowth && area<fMinArea) ){
+ bBest = 1;
+ }
+#endif
+ if( bBest ){
fMinOverlap = overlap;
fMinGrowth = growth;
fMinArea = area;
** the node pNode. This function updates the bounding box cells in
** all ancestor elements.
*/
-static void AdjustTree(
+static int AdjustTree(
Rtree *pRtree, /* Rtree table */
RtreeNode *pNode, /* Adjust ancestry of this node. */
RtreeCell *pCell /* This cell was just inserted */
){
RtreeNode *p = pNode;
while( p->pParent ){
- RtreeCell cell;
RtreeNode *pParent = p->pParent;
- int iCell = nodeParentIndex(pRtree, p);
+ RtreeCell cell;
+ int iCell;
+
+ if( nodeParentIndex(pRtree, p, &iCell) ){
+ return SQLITE_CORRUPT;
+ }
nodeGetCell(pRtree, pParent, iCell, &cell);
if( !cellContains(pRtree, &cell, pCell) ){
p = pParent;
}
+ return SQLITE_OK;
}
/*
nCell++;
if( pNode->iNode==1 ){
- pRight = nodeNew(pRtree, pNode, 1);
- pLeft = nodeNew(pRtree, pNode, 1);
+ pRight = nodeNew(pRtree, pNode);
+ pLeft = nodeNew(pRtree, pNode);
pRtree->iDepth++;
pNode->isDirty = 1;
writeInt16(pNode->zData, pRtree->iDepth);
}else{
pLeft = pNode;
- pRight = nodeNew(pRtree, pLeft->pParent, 1);
+ pRight = nodeNew(pRtree, pLeft->pParent);
nodeReference(pLeft);
}
goto splitnode_out;
}
- /* Ensure both child nodes have node numbers assigned to them. */
- if( (0==pRight->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pRight)))
+ /* Ensure both child nodes have node numbers assigned to them by calling
+ ** nodeWrite(). Node pRight always needs a node number, as it was created
+ ** by nodeNew() above. But node pLeft sometimes already has a node number.
+ ** In this case avoid the all to nodeWrite().
+ */
+ if( SQLITE_OK!=(rc = nodeWrite(pRtree, pRight))
|| (0==pLeft->iNode && SQLITE_OK!=(rc = nodeWrite(pRtree, pLeft)))
){
goto splitnode_out;
}
}else{
RtreeNode *pParent = pLeft->pParent;
- int iCell = nodeParentIndex(pRtree, pLeft);
- nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
- AdjustTree(pRtree, pParent, &leftbbox);
+ int iCell;
+ rc = nodeParentIndex(pRtree, pLeft, &iCell);
+ if( rc==SQLITE_OK ){
+ nodeOverwriteCell(pRtree, pParent, &leftbbox, iCell);
+ rc = AdjustTree(pRtree, pParent, &leftbbox);
+ }
+ if( rc!=SQLITE_OK ){
+ goto splitnode_out;
+ }
}
if( (rc = rtreeInsertCell(pRtree, pRight->pParent, &rightbbox, iHeight+1)) ){
goto splitnode_out;
return rc;
}
+/*
+** If node pLeaf is not the root of the r-tree and its pParent pointer is
+** still NULL, load all ancestor nodes of pLeaf into memory and populate
+** the pLeaf->pParent chain all the way up to the root node.
+**
+** This operation is required when a row is deleted (or updated - an update
+** is implemented as a delete followed by an insert). SQLite provides the
+** rowid of the row to delete, which can be used to find the leaf on which
+** the entry resides (argument pLeaf). Once the leaf is located, this
+** function is called to determine its ancestry.
+*/
static int fixLeafParent(Rtree *pRtree, RtreeNode *pLeaf){
int rc = SQLITE_OK;
- if( pLeaf->iNode!=1 && pLeaf->pParent==0 ){
- sqlite3_bind_int64(pRtree->pReadParent, 1, pLeaf->iNode);
- if( sqlite3_step(pRtree->pReadParent)==SQLITE_ROW ){
- i64 iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
- rc = nodeAcquire(pRtree, iNode, 0, &pLeaf->pParent);
- }else{
- rc = SQLITE_ERROR;
- }
- sqlite3_reset(pRtree->pReadParent);
- if( rc==SQLITE_OK ){
- rc = fixLeafParent(pRtree, pLeaf->pParent);
+ RtreeNode *pChild = pLeaf;
+ while( rc==SQLITE_OK && pChild->iNode!=1 && pChild->pParent==0 ){
+ int rc2 = SQLITE_OK; /* sqlite3_reset() return code */
+ sqlite3_bind_int64(pRtree->pReadParent, 1, pChild->iNode);
+ rc = sqlite3_step(pRtree->pReadParent);
+ if( rc==SQLITE_ROW ){
+ RtreeNode *pTest; /* Used to test for reference loops */
+ i64 iNode; /* Node number of parent node */
+
+ /* Before setting pChild->pParent, test that we are not creating a
+ ** loop of references (as we would if, say, pChild==pParent). We don't
+ ** want to do this as it leads to a memory leak when trying to delete
+ ** the referenced counted node structures.
+ */
+ iNode = sqlite3_column_int64(pRtree->pReadParent, 0);
+ for(pTest=pLeaf; pTest && pTest->iNode!=iNode; pTest=pTest->pParent);
+ if( !pTest ){
+ rc2 = nodeAcquire(pRtree, iNode, 0, &pChild->pParent);
+ }
}
+ rc = sqlite3_reset(pRtree->pReadParent);
+ if( rc==SQLITE_OK ) rc = rc2;
+ if( rc==SQLITE_OK && !pChild->pParent ) rc = SQLITE_CORRUPT;
+ pChild = pChild->pParent;
}
return rc;
}
static int removeNode(Rtree *pRtree, RtreeNode *pNode, int iHeight){
int rc;
+ int rc2;
RtreeNode *pParent;
int iCell;
assert( pNode->nRef==1 );
/* Remove the entry in the parent cell. */
- iCell = nodeParentIndex(pRtree, pNode);
- pParent = pNode->pParent;
- pNode->pParent = 0;
- if( SQLITE_OK!=(rc = deleteCell(pRtree, pParent, iCell, iHeight+1))
- || SQLITE_OK!=(rc = nodeRelease(pRtree, pParent))
- ){
+ rc = nodeParentIndex(pRtree, pNode, &iCell);
+ if( rc==SQLITE_OK ){
+ pParent = pNode->pParent;
+ pNode->pParent = 0;
+ rc = deleteCell(pRtree, pParent, iCell, iHeight+1);
+ }
+ rc2 = nodeRelease(pRtree, pParent);
+ if( rc==SQLITE_OK ){
+ rc = rc2;
+ }
+ if( rc!=SQLITE_OK ){
return rc;
}
return SQLITE_OK;
}
-static void fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
+static int fixBoundingBox(Rtree *pRtree, RtreeNode *pNode){
RtreeNode *pParent = pNode->pParent;
+ int rc = SQLITE_OK;
if( pParent ){
int ii;
int nCell = NCELL(pNode);
cellUnion(pRtree, &box, &cell);
}
box.iRowid = pNode->iNode;
- ii = nodeParentIndex(pRtree, pNode);
- nodeOverwriteCell(pRtree, pParent, &box, ii);
- fixBoundingBox(pRtree, pParent);
+ rc = nodeParentIndex(pRtree, pNode, &ii);
+ if( rc==SQLITE_OK ){
+ nodeOverwriteCell(pRtree, pParent, &box, ii);
+ rc = fixBoundingBox(pRtree, pParent);
+ }
}
+ return rc;
}
/*
** cell, adjust the r-tree data structure if required.
*/
static int deleteCell(Rtree *pRtree, RtreeNode *pNode, int iCell, int iHeight){
+ RtreeNode *pParent;
int rc;
if( SQLITE_OK!=(rc = fixLeafParent(pRtree, pNode)) ){
** cell in the parent node so that it tightly contains the updated
** node.
*/
- if( pNode->iNode!=1 ){
- RtreeNode *pParent = pNode->pParent;
- if( (pParent->iNode!=1 || NCELL(pParent)!=1)
- && (NCELL(pNode)<RTREE_MINCELLS(pRtree))
- ){
+ pParent = pNode->pParent;
+ assert( pParent || pNode->iNode==1 );
+ if( pParent ){
+ if( NCELL(pNode)<RTREE_MINCELLS(pRtree) ){
rc = removeNode(pRtree, pNode, iHeight);
}else{
- fixBoundingBox(pRtree, pNode);
+ rc = fixBoundingBox(pRtree, pNode);
}
}
}
}
if( rc==SQLITE_OK ){
- fixBoundingBox(pRtree, pNode);
+ rc = fixBoundingBox(pRtree, pNode);
}
for(; rc==SQLITE_OK && ii<nCell; ii++){
/* Find a node to store this cell in. pNode->iNode currently contains
rc = SplitNode(pRtree, pNode, pCell, iHeight);
#endif
}else{
- AdjustTree(pRtree, pNode, pCell);
- if( iHeight==0 ){
- rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
- }else{
- rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+ rc = AdjustTree(pRtree, pNode, pCell);
+ if( rc==SQLITE_OK ){
+ if( iHeight==0 ){
+ rc = rowidWrite(pRtree, pCell->iRowid, pNode->iNode);
+ }else{
+ rc = parentWrite(pRtree, pCell->iRowid, pNode->iNode);
+ }
}
}
return rc;
rtreeReference(pRtree);
assert(nData>=1);
- assert(hashIsEmpty(pRtree));
/* If azData[0] is not an SQL NULL value, it is the rowid of a
** record to delete from the r-tree table. The following block does
/* Delete the cell in question from the leaf node. */
if( rc==SQLITE_OK ){
int rc2;
- iCell = nodeRowidIndex(pRtree, pLeaf, iDelete);
- rc = deleteCell(pRtree, pLeaf, iCell, 0);
+ rc = nodeRowidIndex(pRtree, pLeaf, iDelete, &iCell);
+ if( rc==SQLITE_OK ){
+ rc = deleteCell(pRtree, pLeaf, iCell, 0);
+ }
rc2 = nodeRelease(pRtree, pLeaf);
if( rc==SQLITE_OK ){
rc = rc2;
** the root node (the operation that Gutman's paper says to perform
** in this scenario).
*/
- if( rc==SQLITE_OK && pRtree->iDepth>0 ){
- if( rc==SQLITE_OK && NCELL(pRoot)==1 ){
- RtreeNode *pChild;
- i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
- rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
- if( rc==SQLITE_OK ){
- rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
- }
- if( rc==SQLITE_OK ){
- pRtree->iDepth--;
- writeInt16(pRoot->zData, pRtree->iDepth);
- pRoot->isDirty = 1;
- }
+ if( rc==SQLITE_OK && pRtree->iDepth>0 && NCELL(pRoot)==1 ){
+ int rc2;
+ RtreeNode *pChild;
+ i64 iChild = nodeGetRowid(pRtree, pRoot, 0);
+ rc = nodeAcquire(pRtree, iChild, pRoot, &pChild);
+ if( rc==SQLITE_OK ){
+ rc = removeNode(pRtree, pChild, pRtree->iDepth-1);
+ }
+ rc2 = nodeRelease(pRtree, pChild);
+ if( rc==SQLITE_OK ) rc = rc2;
+ if( rc==SQLITE_OK ){
+ pRtree->iDepth--;
+ writeInt16(pRoot->zData, pRtree->iDepth);
+ pRoot->isDirty = 1;
}
}
}
rc = sqlite3_reset(pRtree->pReadRowid);
}
+ *pRowid = cell.iRowid;
if( rc==SQLITE_OK ){
rc = ChooseLeaf(pRtree, &cell, 0, &pLeaf);
Rtree *pRtree;
int nDb; /* Length of string argv[1] */
int nName; /* Length of string argv[2] */
- int eCoordType = (int)pAux;
+ int eCoordType = (pAux ? RTREE_COORD_INT32 : RTREE_COORD_REAL32);
const char *aErrMsg[] = {
0, /* 0 */
** function "rtreenode".
*/
int sqlite3RtreeInit(sqlite3 *db){
- int rc = SQLITE_OK;
+ const int utf8 = SQLITE_UTF8;
+ int rc;
- if( rc==SQLITE_OK ){
- int utf8 = SQLITE_UTF8;
- rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
- }
+ rc = sqlite3_create_function(db, "rtreenode", 2, utf8, 0, rtreenode, 0, 0);
if( rc==SQLITE_OK ){
int utf8 = SQLITE_UTF8;
rc = sqlite3_create_function(db, "rtreedepth", 1, utf8, 0,rtreedepth, 0, 0);
return rc;
}
+/*
+** A version of sqlite3_free() that can be used as a callback. This is used
+** in two places - as the destructor for the blob value returned by the
+** invocation of a geometry function, and as the destructor for the geometry
+** functions themselves.
+*/
+static void doSqlite3Free(void *p){
+ sqlite3_free(p);
+}
+
+/*
+** Each call to sqlite3_rtree_geometry_callback() creates an ordinary SQLite
+** scalar user function. This C function is the callback used for all such
+** registered SQL functions.
+**
+** The scalar user functions return a blob that is interpreted by r-tree
+** table MATCH operators.
+*/
+static void geomCallback(sqlite3_context *ctx, int nArg, sqlite3_value **aArg){
+ RtreeGeomCallback *pGeomCtx = (RtreeGeomCallback *)sqlite3_user_data(ctx);
+ RtreeMatchArg *pBlob;
+ int nBlob;
+
+ nBlob = sizeof(RtreeMatchArg) + (nArg-1)*sizeof(double);
+ pBlob = (RtreeMatchArg *)sqlite3_malloc(nBlob);
+ if( !pBlob ){
+ sqlite3_result_error_nomem(ctx);
+ }else{
+ int i;
+ pBlob->magic = RTREE_GEOMETRY_MAGIC;
+ pBlob->xGeom = pGeomCtx->xGeom;
+ pBlob->pContext = pGeomCtx->pContext;
+ pBlob->nParam = nArg;
+ for(i=0; i<nArg; i++){
+ pBlob->aParam[i] = sqlite3_value_double(aArg[i]);
+ }
+ sqlite3_result_blob(ctx, pBlob, nBlob, doSqlite3Free);
+ }
+}
+
+/*
+** Register a new geometry function for use with the r-tree MATCH operator.
+*/
+int sqlite3_rtree_geometry_callback(
+ sqlite3 *db,
+ const char *zGeom,
+ int (*xGeom)(sqlite3_rtree_geometry *, int, double *, int *),
+ void *pContext
+){
+#if 0
+ RtreeGeomCallback *pGeomCtx; /* Context object for new user-function */
+
+ /* Allocate and populate the context object. */
+ pGeomCtx = (RtreeGeomCallback *)sqlite3_malloc(sizeof(RtreeGeomCallback));
+ if( !pGeomCtx ) return SQLITE_NOMEM;
+ pGeomCtx->xGeom = xGeom;
+ pGeomCtx->pContext = pContext;
+
+ /* Create the new user-function. Register a destructor function to delete
+ ** the context object when it is no longer required. */
+ return sqlite3_create_function_v2(db, zGeom, -1, SQLITE_ANY,
+ (void *)pGeomCtx, geomCallback, 0, 0, doSqlite3Free
+ );
+#endif
+ return SQLITE_MISUSE;
+}
+
#if !SQLITE_CORE
int sqlite3_extension_init(
sqlite3 *db,
projects / thirdparty / sqlite.git / commitdiff
