Experimental changes that allow a WITHOUT ROWID virtual table to be writable

as long as it has only a single-column PRIMARY KEY.

FossilOrigin-Name: ab9ee4c1e64c09c7130e385a23d043d78bad95dff5509c7adc9b992350a4a537

3 files changed, 29 insertions, 8 deletions

diff --git a/src/delete.c b/src/delete.c
index bf320fe7e..cd78f68f4 100644
--- a/src/delete.c
+++ b/src/delete.c
@@ -502,7 +502,11 @@ void sqlite3DeleteFrom(
       }
     }else if( pPk ){
       addrLoop = sqlite3VdbeAddOp1(v, OP_Rewind, iEphCur); VdbeCoverage(v);
-      sqlite3VdbeAddOp2(v, OP_RowData, iEphCur, iKey);
+      if( IsVirtual(pTab) ){
+        sqlite3VdbeAddOp3(v, OP_Column, iEphCur, 0, iKey);
+      }else{
+        sqlite3VdbeAddOp2(v, OP_RowData, iEphCur, iKey);
+      }
       assert( nKey==0 );  /* OP_Found will use a composite key */
     }else{
       addrLoop = sqlite3VdbeAddOp3(v, OP_RowSetRead, iRowSet, 0, iKey);
diff --git a/src/update.c b/src/update.c
index fa8885be6..e69efdb6b 100644
--- a/src/update.c
+++ b/src/update.c
@@ -803,12 +803,6 @@ static void updateVirtualTable(
   if( pWInfo==0 ) return;
 
   /* Populate the argument registers. */
-  sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg);
-  if( pRowid ){
-    sqlite3ExprCode(pParse, pRowid, regArg+1);
-  }else{
-    sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg+1);
-  }
   for(i=0; i<pTab->nCol; i++){
     if( aXRef[i]>=0 ){
       sqlite3ExprCode(pParse, pChanges->a[aXRef[i]].pExpr, regArg+2+i);
@@ -816,6 +810,23 @@ static void updateVirtualTable(
       sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, i, regArg+2+i);
     }
   }
+  if( HasRowid(pTab) ){
+    sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg);
+    if( pRowid ){
+      sqlite3ExprCode(pParse, pRowid, regArg+1);
+    }else{
+      sqlite3VdbeAddOp2(v, OP_Rowid, iCsr, regArg+1);
+    }
+  }else{
+    Index *pPk;   /* PRIMARY KEY index */
+    i16 iPk;      /* PRIMARY KEY column */
+    pPk = sqlite3PrimaryKeyIndex(pTab);
+    assert( pPk!=0 );
+    assert( pPk->nKeyCol==1 );
+    iPk = pPk->aiColumn[0];
+    sqlite3VdbeAddOp3(v, OP_VColumn, iCsr, iPk, regArg);
+    sqlite3VdbeAddOp2(v, OP_SCopy, regArg+2+iPk, regArg+1);
+  }
 
   bOnePass = sqlite3WhereOkOnePass(pWInfo, aDummy);
 
diff --git a/src/vtab.c b/src/vtab.c
index e76bcf323..634dccc03 100644
--- a/src/vtab.c
+++ b/src/vtab.c
@@ -773,7 +773,13 @@ int sqlite3_declare_vtab(sqlite3 *db, const char *zCreateTable){
       pNew->nCol = 0;
       pNew->aCol = 0;
       assert( pTab->pIndex==0 );
-      if( !HasRowid(pNew) && pCtx->pVTable->pMod->pModule->xUpdate!=0 ){
+      assert( HasRowid(pNew) || sqlite3PrimaryKeyIndex(pNew)!=0 );
+      if( !HasRowid(pNew)
+       && pCtx->pVTable->pMod->pModule->xUpdate!=0
+       && sqlite3PrimaryKeyIndex(pNew)->nKeyCol!=1
+      ){
+        /* WITHOUT ROWID virtual tables must either be read-only (xUpdate==0)
+        ** or else must have a single-column PRIMARY KEY */
         rc = SQLITE_ERROR;
       }
       pIdx = pNew->pIndex;