**
** The schema of the virtual table is this:
**
-** CREATE TABLE qpvtab(a,b,c,d,e, f,g,h,i,j, k,l,m,n,o, p,q,r,s,t);
+** CREATE TABLE qpvtab(
+** vn TEXT, -- Name of an sqlite3_index_info field
+** ix INTEGER, -- Array index or value
+** cn TEXT, -- Column name
+** op INTEGER, -- operator
+** ux BOOLEAN, -- "usable" field
+** rhs TEXT, -- sqlite3_vtab_rhs_value()
**
-** There is also a HIDDEN column "flags".
+** a, b, c, d, e, -- Extra columns to attach constraints to
**
-** All columns except column "a" have a value that is either TEXT that
-** is there name, or INTEGER which is their index (b==1). TEXT is the
-** default, but INTEGER is used of there is a constraint on flags where the
-** right-hand side is an integer that includes the 1 bit.
+** flags INTEGER HIDDEN -- control flags
+** );
**
-** The "a" column returns text that describes one of the parameters that
-** xBestIndex was called with. A completely query of the table should
-** show all details of how xBestIndex was called.
+** The virtual table returns a description of the sqlite3_index_info object
+** that was provided to the (successful) xBestIndex method. There is one
+** row in the result table for each field in the sqlite3_index_info object.
+**
+** The values of the "a" through "e" columns are one of:
+**
+** 1. TEXT - the same as the column name
+** 2. INTEGER - 1 for "a", 2 for "b", and so forth
+**
+** Option 1 is the default behavior. 2 is use if there is a usable
+** constraint on "flags" with an integer right-hand side that where the
+** value of the right-hand side has its 0x01 bit set.
+**
+** All constraints on columns "a" through "e" are marked as "omit".
+**
+** If there is a usable constraint on "flags" that has a RHS value that
+** is an integer and that integer has its 0x02 bit set, then the
+** orderByConsumed flag is set.
+**
+** COMPILE:
+**
+** gcc -Wall -g -shared -fPIC -I. qpvtab.c -o qqvtab.so
+**
+** EXAMPLE USAGE:
+**
+** .load ./qpvtab
+** SELECT rowid, *, flags FROM qpvtab(102)
+** WHERE a=19
+** AND b BETWEEN 4.5 and 'hello'
+** AND c<>x'aabbcc'
+** ORDER BY d, e DESC;
*/
#if !defined(SQLITEINT_H)
#include "sqlite3ext.h"
SQLITE_EXTENSION_INIT1
#include <string.h>
#include <assert.h>
+#include <stdlib.h>
#if !defined(SQLITE_OMIT_VIRTUALTABLE)
int flags; /* Flags value */
};
+/*
+** Names of columns
+*/
+static const char *azColname[] = {
+ "vn",
+ "ix",
+ "cn",
+ "op",
+ "ux",
+ "rhs",
+ "a", "b", "c", "d", "e",
+ "flags"
+};
+
/*
** The qpvtabConnect() method is invoked to create a new
** qpvtab virtual table.
int rc;
rc = sqlite3_declare_vtab(db,
- "CREATE TABLE x(a,b,c,d,e, f,g,h,i,j, k,l,m,n,o, p,q,r,s,t,"
- " flags HIDDEN)"
+ "CREATE TABLE x("
+ " vn TEXT,"
+ " ix INT,"
+ " cn TEXT,"
+ " op INT,"
+ " ux BOOLEAN,"
+ " rhs TEXT,"
+ " a, b, c, d, e,"
+ " flags INT HIDDEN)"
);
-#define QPVTAB_A 0
-#define QPVTAB_B 1
-#define QPVTAB_T 19
-#define QPVTAB_FLAGS 20
+#define QPVTAB_VN 0
+#define QPVTAB_IX 1
+#define QPVTAB_CN 2
+#define QPVTAB_OP 3
+#define QPVTAB_UX 4
+#define QPVTAB_RHS 5
+#define QPVTAB_A 6
+#define QPVTAB_B 7
+#define QPVTAB_C 8
+#define QPVTAB_D 9
+#define QPVTAB_E 10
+#define QPVTAB_FLAGS 11
if( rc==SQLITE_OK ){
pNew = sqlite3_malloc( sizeof(*pNew) );
*ppVtab = (sqlite3_vtab*)pNew;
*/
static int qpvtabNext(sqlite3_vtab_cursor *cur){
qpvtab_cursor *pCur = (qpvtab_cursor*)cur;
- while( pCur->iRowid<pCur->nData && pCur->zData[pCur->iRowid]!='\n' ){
- pCur->iRowid++;
+ if( pCur->iRowid<pCur->nData ){
+ const char *z = &pCur->zData[pCur->iRowid];
+ const char *zEnd = strchr(z, '\n');
+ if( zEnd ) zEnd++;
+ pCur->iRowid = (int)(zEnd - pCur->zData);
}
- if( pCur->zData[pCur->iRowid]=='\n' ) pCur->iRowid++;
return SQLITE_OK;
}
int i /* Which column to return */
){
qpvtab_cursor *pCur = (qpvtab_cursor*)cur;
- if( i==0 && pCur->iRowid<pCur->nData ){
+ if( i>=QPVTAB_VN && i<=QPVTAB_RHS && pCur->iRowid<pCur->nData ){
+ const char *z = &pCur->zData[pCur->iRowid];
+ const char *zEnd;
int j;
- for(j=pCur->iRowid; j<pCur->nData && pCur->zData[j]!='\n'; j++){}
- sqlite3_result_text64(ctx, &pCur->zData[pCur->iRowid], j-pCur->iRowid,
- SQLITE_TRANSIENT, SQLITE_UTF8);
- }else if( i>=QPVTAB_B && i<=QPVTAB_T ){
+ j = QPVTAB_VN;
+ while(1){
+ zEnd = strchr(z, j==QPVTAB_RHS ? '\n' : ',');
+ if( j==i || zEnd==0 ) break;
+ z = zEnd+1;
+ j++;
+ }
+ if( zEnd==z ){
+ sqlite3_result_null(ctx);
+ }else if( i==QPVTAB_IX || i==QPVTAB_OP || i==QPVTAB_UX ){
+ sqlite3_result_int(ctx, atoi(z));
+ }else{
+ sqlite3_result_text64(ctx, z, zEnd-z, SQLITE_TRANSIENT, SQLITE_UTF8);
+ }
+ }else if( i>=QPVTAB_A && i<=QPVTAB_E ){
if( pCur->flags & 1 ){
- sqlite3_result_int(ctx, i);
+ sqlite3_result_int(ctx, i-QPVTAB_A+1);
}else{
- char x = 'a'+i;
+ char x = 'a'+i-QPVTAB_A;
sqlite3_result_text64(ctx, &x, 1, SQLITE_TRANSIENT, SQLITE_UTF8);
}
}else if( i==QPVTAB_FLAGS ){
case SQLITE_FLOAT:
sqlite3_str_appendf(pStr, "%f", sqlite3_value_double(pVal));
break;
- case SQLITE_TEXT:
- sqlite3_str_appendf(pStr, "%Q", sqlite3_value_text(pVal));
+ case SQLITE_TEXT: {
+ int i;
+ const char *a = (const char*)sqlite3_value_text(pVal);
+ int n = sqlite3_value_bytes(pVal);
+ sqlite3_str_append(pStr, "'", 1);
+ for(i=0; i<n; i++){
+ char c = a[i];
+ if( c=='\n' ) c = ' ';
+ sqlite3_str_append(pStr, &c, 1);
+ if( c=='\'' ) sqlite3_str_append(pStr, &c, 1);
+ }
+ sqlite3_str_append(pStr, "'", 1);
break;
+ }
case SQLITE_BLOB: {
int i;
const unsigned char *a = sqlite3_value_blob(pVal);
){
sqlite3_str *pStr = sqlite3_str_new(0);
int i, k = 0;
- sqlite3_str_appendf(pStr, "nConstraint=%d\n", pIdxInfo->nConstraint);
+ sqlite3_str_appendf(pStr, "nConstraint,%d,,,,\n", pIdxInfo->nConstraint);
for(i=0; i<pIdxInfo->nConstraint; i++){
sqlite3_value *pVal;
int iCol = pIdxInfo->aConstraint[i].iColumn;
- char zCol[8];
- if( iCol==QPVTAB_FLAGS ){
- strcpy(zCol, "flags");
- if( pIdxInfo->aConstraint[i].usable ){
- pVal = 0;
- sqlite3_vtab_rhs_value(pIdxInfo, i, &pVal);
- if( pVal ){
- pIdxInfo->idxNum = sqlite3_value_int(pVal);
- }
+ if( iCol==QPVTAB_FLAGS && pIdxInfo->aConstraint[i].usable ){
+ pVal = 0;
+ sqlite3_vtab_rhs_value(pIdxInfo, i, &pVal);
+ if( pVal ){
+ pIdxInfo->idxNum = sqlite3_value_int(pVal);
+ if( pIdxInfo->idxNum & 2 ) pIdxInfo->orderByConsumed = 1;
}
- }else{
- zCol[0] = iCol+'a';
- zCol[1] = 0;
}
- sqlite3_str_appendf(pStr,"aConstraint[%d]: iColumn=%s op=%d usable=%d",
+ sqlite3_str_appendf(pStr,"aConstraint,%d,%s,%d,%d,",
i,
- zCol,
+ azColname[iCol],
pIdxInfo->aConstraint[i].op,
pIdxInfo->aConstraint[i].usable);
pVal = 0;
sqlite3_vtab_rhs_value(pIdxInfo, i, &pVal);
if( pVal ){
- sqlite3_str_appendf(pStr, " value=");
qpvtabStrAppendValue(pStr, pVal);
}
sqlite3_str_append(pStr, "\n", 1);
- if( pIdxInfo->aConstraint[i].usable ){
+ if( iCol>=QPVTAB_A && pIdxInfo->aConstraint[i].usable ){
pIdxInfo->aConstraintUsage[i].argvIndex = ++k;
pIdxInfo->aConstraintUsage[i].omit = 1;
}
}
+ sqlite3_str_appendf(pStr, "nOrderBy,%d,,,,\n", pIdxInfo->nOrderBy);
+ for(i=0; i<pIdxInfo->nOrderBy; i++){
+ int iCol = pIdxInfo->aOrderBy[i].iColumn;
+ sqlite3_str_appendf(pStr, "aOrderBy,%d,%s,%d,,\n",i,
+ iCol>=0 ? azColname[iCol] : "rowid",
+ pIdxInfo->aOrderBy[i].desc
+ );
+ }
+ sqlite3_str_appendf(pStr, "idxFlags,%d,,,,\n", pIdxInfo->idxFlags);
+ sqlite3_str_appendf(pStr, "colUsed,%d,,,,\n", (int)pIdxInfo->colUsed);
pIdxInfo->estimatedCost = (double)10;
pIdxInfo->estimatedRows = 10;
- sqlite3_str_appendf(pStr, "idxNum=%d\n", pIdxInfo->idxNum);
+ sqlite3_str_appendf(pStr, "idxNum,%d,,,,\n", pIdxInfo->idxNum);
+ sqlite3_str_appendf(pStr, "orderByConsumed,%d,,,,\n",
+ pIdxInfo->orderByConsumed);
pIdxInfo->idxStr = sqlite3_str_finish(pStr);
pIdxInfo->needToFreeIdxStr = 1;
return SQLITE_OK;
projects / thirdparty / sqlite.git / commitdiff
