Add the -withoutnulls option to the "db eval" method in the TCL interface.

FossilOrigin-Name: 18f0616e15684ca327fb10a1d133331af1d3b75f609498982290f6ad69fcaced

manifest

@@ -1,5 +1,5 @@
-C The\s".import"\scommand\sof\sthe\sshell,\sand\sthe\scsv\svirtual\stable\sextension\sboth\nignore\sa\ssingle\sUTF-8\sBOM\sat\sthe\sbeginning\sof\stheir\sinput.
-D 2017-06-26T18:42:23.729
+C Add\sthe\s-withoutnulls\soption\sto\sthe\s"db\seval"\smethod\sin\sthe\sTCL\sinterface.
+D 2017-06-26T21:08:32.812
 F Makefile.in 1cc758ce3374a32425e4d130c2fe7b026b20de5b8843243de75f087c0a2661fb
 F Makefile.linux-gcc 7bc79876b875010e8c8f9502eb935ca92aa3c434
 F Makefile.msc 8eeb80162074004e906b53d7340a12a14c471a83743aab975947e95ce061efcc
@@ -414,7 +414,7 @@ F src/sqliteInt.h 34a54fb47de2da1465f3d3ba1cd373db880bd5d588b0fe862a073ecacd6dda
 F src/sqliteLimit.h 1513bfb7b20378aa0041e7022d04acb73525de35b80b252f1b83fedb4de6a76b
 F src/status.c a9e66593dfb28a9e746cba7153f84d49c1ddc4b1
 F src/table.c b46ad567748f24a326d9de40e5b9659f96ffff34
-F src/tclsqlite.c 1ac29f18b1b3787a30b45dbbdf6fdc4aa4f1a2f8c7c8fe586beba1b177eba97d
+F src/tclsqlite.c cbf6313f86400acdf7dbf55fcd218cd28d43110a1210967efbc4f250646f81c0
 F src/test1.c c99f0442918a7a5d5b68a95d6024c211989e6c782c15ced5a558994baaf76a5e
 F src/test2.c 3efb99ab7f1fc8d154933e02ae1378bac9637da5
 F src/test3.c b8434949dfb8aff8dfa082c8b592109e77844c2135ed3c492113839b6956255b
@@ -1187,7 +1187,7 @@ F test/tabfunc01.test 699251cb99651415218a891384510a685c7ab012
 F test/table.test b708f3e5fa2542fa51dfab21fc07b36ea445cb2f
 F test/tableapi.test 2674633fa95d80da917571ebdd759a14d9819126
 F test/tableopts.test dba698ba97251017b7c80d738c198d39ab747930
-F test/tclsqlite.test 1d73b9203b1ca8798d7d7310742b8d3febc0d56e
+F test/tclsqlite.test c3d7ac9449634b9f17fd048a3c0212e88a7448be810a9c5bd051acc1ffa00d2f
 F test/tempdb.test bd92eba8f20e16a9136e434e20b280794de3cdb6
 F test/tempdb2.test 27e41ed540b2f9b056c2e77e9bddc1b875358507
 F test/tempfault.test 0c0d349c9a99bf5f374655742577f8712c647900
@@ -1583,7 +1583,7 @@ F vsixtest/vsixtest.tcl 6a9a6ab600c25a91a7acc6293828957a386a8a93
 F vsixtest/vsixtest.vcxproj.data 2ed517e100c66dc455b492e1a33350c1b20fbcdc
 F vsixtest/vsixtest.vcxproj.filters 37e51ffedcdb064aad6ff33b6148725226cd608e
 F vsixtest/vsixtest_TemporaryKey.pfx e5b1b036facdb453873e7084e1cae9102ccc67a0
-P c8186874b3fec737445ad5c4ba3eaecd922af664b387d89dc31eea60476a0294
-R ab3f395a40974200838735f2b7274cd8
+P 7c15d762d99c2e3e534cd35dfe25ddcd317637eb1f2655fd24c2dd5f9d5a7613
+R 444ece00921d566093c338ff4adc8e5d
 U drh
-Z 910f6f462fbe04fd9eb737726ef5f52f
+Z eb4d6ea47810159e5e12ebef5223a855

manifest.uuid

@@ -1 +1 @@
-7c15d762d99c2e3e534cd35dfe25ddcd317637eb1f2655fd24c2dd5f9d5a7613
+18f0616e15684ca327fb10a1d133331af1d3b75f609498982290f6ad69fcaced

src/tclsqlite.c

@@ -1451,10 +1451,13 @@ struct DbEvalContext {
   const char *zSql;               /* Remaining SQL to execute */
   SqlPreparedStmt *pPreStmt;      /* Current statement */
   int nCol;                       /* Number of columns returned by pStmt */
+  int evalFlags;                  /* Flags used */
   Tcl_Obj *pArray;                /* Name of array variable */
   Tcl_Obj **apColName;            /* Array of column names */
 };
 
+#define SQLITE_EVAL_WITHOUTNULLS  0x00001  /* Unset array(*) for NULL */
+
 /*
 ** Release any cache of column names currently held as part of
 ** the DbEvalContext structure passed as the first argument.
@@ -1487,7 +1490,8 @@ static void dbEvalInit(
   DbEvalContext *p,               /* Pointer to structure to initialize */
   SqliteDb *pDb,                  /* Database handle */
   Tcl_Obj *pSql,                  /* Object containing SQL script */
-  Tcl_Obj *pArray                 /* Name of Tcl array to set (*) element of */
+  Tcl_Obj *pArray,                /* Name of Tcl array to set (*) element of */
+  int evalFlags                   /* Flags controlling evaluation */
 ){
   memset(p, 0, sizeof(DbEvalContext));
   p->pDb = pDb;
@@ -1498,6 +1502,7 @@ static void dbEvalInit(
     p->pArray = pArray;
     Tcl_IncrRefCount(pArray);
   }
+  p->evalFlags = evalFlags;
 }
 
 /*
@@ -1730,11 +1735,15 @@ static int SQLITE_TCLAPI DbEvalNextCmd(
     Tcl_Obj **apColName;
     dbEvalRowInfo(p, &nCol, &apColName);
     for(i=0; i<nCol; i++){
-      Tcl_Obj *pVal = dbEvalColumnValue(p, i);
       if( pArray==0 ){
-        Tcl_ObjSetVar2(interp, apColName[i], 0, pVal, 0);
+        Tcl_ObjSetVar2(interp, apColName[i], 0, dbEvalColumnValue(p,i), 0);
+      }else if( (p->evalFlags & SQLITE_EVAL_WITHOUTNULLS)!=0
+             && sqlite3_column_type(p->pPreStmt->pStmt, i)==SQLITE_NULL 
+      ){
+        Tcl_UnsetVar2(interp, Tcl_GetString(pArray), 
+                      Tcl_GetString(apColName[i]), 0);
       }else{
-        Tcl_ObjSetVar2(interp, pArray, apColName[i], pVal, 0);
+        Tcl_ObjSetVar2(interp, pArray, apColName[i], dbEvalColumnValue(p,i), 0);
       }
     }
 
@@ -2447,7 +2456,7 @@ static int SQLITE_TCLAPI DbObjCmd(
       return TCL_ERROR;
     }
 
-    dbEvalInit(&sEval, pDb, objv[2], 0);
+    dbEvalInit(&sEval, pDb, objv[2], 0, 0);
     rc = dbEvalStep(&sEval);
     if( choice==DB_ONECOLUMN ){
       if( rc==TCL_OK ){
@@ -2468,7 +2477,7 @@ static int SQLITE_TCLAPI DbObjCmd(
   }
 
   /*
-  **    $db eval $sql ?array? ?{  ...code... }?
+  **    $db eval ?options? $sql ?array? ?{  ...code... }?
   **
   ** The SQL statement in $sql is evaluated.  For each row, the values are
   ** placed in elements of the array named "array" and ...code... is executed.
@@ -2477,8 +2486,22 @@ static int SQLITE_TCLAPI DbObjCmd(
   ** that have the same name as the fields extracted by the query.
   */
   case DB_EVAL: {
+    int evalFlags = 0;
+    const char *zOpt;
+    while( objc>3 && (zOpt = Tcl_GetString(objv[2]))!=0 && zOpt[0]=='-' ){
+      if( strcmp(zOpt, "-withoutnulls")==0 ){
+        evalFlags |= SQLITE_EVAL_WITHOUTNULLS;
+      }
+      else{
+        Tcl_AppendResult(interp, "unknown option: \"", zOpt, "\"", (void*)0);
+        return TCL_ERROR;
+      }
+      objc--;
+      objv++;
+    }
     if( objc<3 || objc>5 ){
-      Tcl_WrongNumArgs(interp, 2, objv, "SQL ?ARRAY-NAME? ?SCRIPT?");
+      Tcl_WrongNumArgs(interp, 2, objv, 
+          "?OPTIONS? SQL ?ARRAY-NAME? ?SCRIPT?");
       return TCL_ERROR;
     }
 
@@ -2486,7 +2509,7 @@ static int SQLITE_TCLAPI DbObjCmd(
       DbEvalContext sEval;
       Tcl_Obj *pRet = Tcl_NewObj();
       Tcl_IncrRefCount(pRet);
-      dbEvalInit(&sEval, pDb, objv[2], 0);
+      dbEvalInit(&sEval, pDb, objv[2], 0, 0);
       while( TCL_OK==(rc = dbEvalStep(&sEval)) ){
         int i;
         int nCol;
@@ -2507,14 +2530,14 @@ static int SQLITE_TCLAPI DbObjCmd(
       Tcl_Obj *pArray = 0;
       Tcl_Obj *pScript;
 
-      if( objc==5 && *(char *)Tcl_GetString(objv[3]) ){
+      if( objc>=5 && *(char *)Tcl_GetString(objv[3]) ){
         pArray = objv[3];
       }
       pScript = objv[objc-1];
       Tcl_IncrRefCount(pScript);
 
       p = (DbEvalContext *)Tcl_Alloc(sizeof(DbEvalContext));
-      dbEvalInit(p, pDb, objv[2], pArray);
+      dbEvalInit(p, pDb, objv[2], pArray, evalFlags);
 
       cd2[0] = (void *)p;
       cd2[1] = (void *)pScript;

test/tclsqlite.test

@@ -113,7 +113,7 @@ ifcapable {complete} {
 do_test tcl-1.14 {
   set v [catch {db eval} msg]
   lappend v $msg
-} {1 {wrong # args: should be "db eval SQL ?ARRAY-NAME? ?SCRIPT?"}}
+} {1 {wrong # args: should be "db eval ?OPTIONS? SQL ?ARRAY-NAME? ?SCRIPT?"}}
 do_test tcl-1.15 {
   set v [catch {db function} msg]
   lappend v $msg
@@ -665,6 +665,44 @@ do_test tcl-15.5 {
 } {0}
 
 
+# 2017-06-26: The --withoutnulls flag to "db eval".
+#
+# In the "db eval --withoutnulls SQL ARRAY" form, NULL results cause the
+# corresponding array entry to be unset.  The default behavior (without
+# the -withoutnulls flags) is for the corresponding array value to get
+# the [db nullvalue] string.
+#
+catch {db close}
+forcedelete test.db
+sqlite3 db test.db
+do_execsql_test tcl-16.100 {
+  CREATE TABLE t1(a,b);
+  INSERT INTO t1 VALUES(1,2),(2,NULL),(3,'xyz');
+}
+do_test tcl-16.101 {
+  set res {}
+  unset -nocomplain x
+  db eval {SELECT * FROM t1} x {
+    lappend res $x(a) [array names x]
+  }
+  set res
+} {1 {a b *} 2 {a b *} 3 {a b *}}
+do_test tcl-16.102 {
+  set res [catch {
+    db eval -unknown {SELECT * FROM t1} x {
+      lappend res $x(a) [array names x]
+    }
+  } rc]
+  lappend res $rc
+} {1 {unknown option: "-unknown"}}
+do_test tcl-16.103 {
+  set res {}
+  unset -nocomplain x
+  db eval -withoutnulls {SELECT * FROM t1} x {
+    lappend res $x(a) [array names x]
+  }
+  set res
+} {1 {a b *} 2 {a *} 3 {a b *}}