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

FossilOrigin-Name: 18f0616e15684ca327fb10a1d133331af1d3b75f609498982290f6ad69fcaced

1 files changed, 33 insertions, 10 deletions

diff --git a/src/tclsqlite.c b/src/tclsqlite.c
index bb7c9e5b8..2ef929609 100644
--- a/src/tclsqlite.c
+++ b/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;