UnQL

static int shellRead(Shell *p, int argc, char **argv){
  if( argc>=2 ){
    int nErr = p->nErr;
    String newFile;
    char *zNew;
    xjd1StringInit(&newFile, 0, 0);
    if( argv[1][0]=='/' || strcmp(p->zFile,"-")==0 ){
      xjd1StringAppend(&newFile, argv[1], 0);
    }else{
      int i, j;
      for(i=j=0; p->zFile[i]; i++){ if( p->zFile[i]=='/' ) j = i; }
      xjd1StringAppendF(&newFile, "%.*s/%s", j, p->zFile, argv[1]);
    }
    zNew = xjd1StringText(&newFile);
    printf("BEGIN %s\n", zNew);

static int shellRead(Shell *p, int argc, char **argv){
  if( argc>=2 ){
    int nErr = p->nErr;
    String newFile;
    char *zNew;
    xjd1StringInit(&newFile, 0, 0);
    if( argv[1][0]=='/' || strcmp(p->zFile,"-")==0 ){
      xjd1StringAppend(&newFile, argv[1], -1);
    }else{
      int i, j;
      for(i=j=0; p->zFile[i]; i++){ if( p->zFile[i]=='/' ) j = i; }
      xjd1StringAppendF(&newFile, "%.*s/%s", j, p->zFile, argv[1]);
    }
    zNew = xjd1StringText(&newFile);
    printf("BEGIN %s\n", zNew);

*************************************************************************
** Code to evaluate an UPDATE statement
*/
#include "xjd1Int.h"


/*
** pBase is a JSON structure object.  Or if it is not, it should be

** converted into one.  Then lookup or insert the zField element.
*/
static JsonNode *findStructElement(JsonNode *pBase, const char *zField){
  JsonStructElem *pElem;
  if( pBase==0 ) return 0;
  if( pBase->eJType!=XJD1_STRUCT ){

    xjd1JsonToNull(pBase);
    pBase->eJType = XJD1_STRUCT;
    pBase->u.st.pFirst = 0;
    pBase->u.st.pLast = 0;
  }
  for(pElem=pBase->u.st.pFirst; pElem; pElem=pElem->pNext){
    if( strcmp(pElem->zLabel, zField)==0 ){
................................................................................

    /* The x[y] operator. The result depends on the type of value x.
    **
    ** If x is of type XJD1_STRUCT, then expression y is converted to
    ** a string. The reference node is property y of object x.
    **
    ** If x is of type XJD1_ARRAY, then expression y is converted to
    ** a number. If that number is an integer, then reference node is
    ** element y of array x. ** TBD: extending array size as needed **
    **
    ** If x is of type XJD1_STRING, then it is treated as an array of 
    ** characters. Processing proceeds as for XJD1_ARRAY. ** TBD **


    */
    case TK_LB: {
      JsonNode *pBase = findOrCreateJsonNode(pRoot, p->u.bi.pLeft);
      switch( pBase->eJType ){
        case XJD1_STRUCT: {
          JsonNode *pRes;
          String idx;
................................................................................
        }

        case XJD1_ARRAY: {
          double rRight;
          int iIdx;
          if( xjd1JsonToReal(xjd1ExprEval(p->u.bi.pRight), &rRight) ) break;
          iIdx = (int)rRight;
          if( (double)iIdx==rRight && iIdx>=0 && iIdx<pBase->u.ar.nElem ){

            return pBase->u.ar.apElem[iIdx];














            



          }
          break;
        }

        case XJD1_STRING: {
          /* TBD */
          break;
        }
      }
    }
    break;
      
    case TK_ID: {

*************************************************************************
** Code to evaluate an UPDATE statement
*/
#include "xjd1Int.h"


/*
** pBase is a JSON structure object.  If it is not, overwrite the current
** value with an empty structure object. [[TBD: If it is not, return 0;]]
** Otherwise, lookup or insert the zField element.
*/
static JsonNode *findStructElement(JsonNode *pBase, const char *zField){
  JsonStructElem *pElem;
  if( pBase==0 ) return 0;
  if( pBase->eJType!=XJD1_STRUCT ){
//    return 0;
    xjd1JsonToNull(pBase);
    pBase->eJType = XJD1_STRUCT;
    pBase->u.st.pFirst = 0;
    pBase->u.st.pLast = 0;
  }
  for(pElem=pBase->u.st.pFirst; pElem; pElem=pElem->pNext){
    if( strcmp(pElem->zLabel, zField)==0 ){
................................................................................

    /* The x[y] operator. The result depends on the type of value x.
    **
    ** If x is of type XJD1_STRUCT, then expression y is converted to
    ** a string. The reference node is property y of object x.
    **
    ** If x is of type XJD1_ARRAY, then expression y is converted to
    ** a number. If that number is an integer, then the reference node
    ** is element y of array x. Grow the array as needed.
    **
    ** If x is of any other type the assignment is silently ignored.
    ** Note that individual string characters can be read, but not
    ** written using the x[y] syntax. 
    ** TBD: should x===null throw an error?
    */
    case TK_LB: {
      JsonNode *pBase = findOrCreateJsonNode(pRoot, p->u.bi.pLeft);
      switch( pBase->eJType ){
        case XJD1_STRUCT: {
          JsonNode *pRes;
          String idx;
................................................................................
        }

        case XJD1_ARRAY: {
          double rRight;
          int iIdx;
          if( xjd1JsonToReal(xjd1ExprEval(p->u.bi.pRight), &rRight) ) break;
          iIdx = (int)rRight;
          if( (double)iIdx==rRight && iIdx>=0 ){
            if( iIdx<pBase->u.ar.nElem ){
              return pBase->u.ar.apElem[iIdx];
            }else{
              JsonNode **pNewArray;
              int i;
              /* Grow the array as needed. TBD: find a way to handle very
              ** large, sparse arrays. As a temporary drafting precaution,
              ** assert that the value of iIdx is less than 1024. 
              */
              assert( iIdx<1024 );
              pNewArray = xjd1_realloc(pBase->u.ar.apElem, sizeof(JsonNode*)*(iIdx+1));
              if( pNewArray==0 ) break;
              pBase->u.ar.apElem = pNewArray;
              for(i=pBase->u.ar.nElem; i<=iIdx; i++) {
                pNewArray[i] = xjd1JsonNew(0);
                pNewArray[i]->eJType = XJD1_NULL;
              }
              pBase->u.ar.nElem = iIdx+1;
              return pBase->u.ar.apElem[iIdx];
            }
          }
          break;
        }

        case XJD1_NULL: {
          /* TBD: throw error? */
          break;
        }
      }
    }
    break;
      
    case TK_ID: {

-- Test UPDATE statement
--

.new t1.db
CREATE COLLECTION c1;
INSERT INTO c1 VALUE null;
INSERT INTO c1 VALUE true;
INSERT INTO c1 VALUE 1;
INSERT INTO c1 VALUE "abc";
INSERT INTO c1 VALUE [1,2,3,4];
INSERT INTO c1 VALUE {a: 1, b:2, c:3};

.testcase 0
SELECT FROM c1;
.json null\
      true\
      1\
      "abc"\
      [1,2,3,4]\
      {"a":1,"b":2,"c":3}

-- setting named properties on primitives or
-- arrays is ignored
.testcase 1
UPDATE c1 SET c1.a = 2;
SELECT FROM c1;
.json null\
      true\
      1\
      "abc"\
      [1,2,3,4]\
      {"a":2,"b":2,"c":3}

-- setting named properties on primitives or
-- arrays is ignored, also when x[y] syntax is used
.testcase 2
UPDATE c1 SET c1["a"] = 3;
SELECT FROM c1;
.json null\
      true\
      1\
      "abc"\
      [1,2,3,4]\
      {"a":3,"b":2,"c":3}

-- setting number properties on primitives is
-- ignored, but honoured on arrays and objects
.testcase 3
UPDATE c1 SET c1["2"] = 7;
SELECT FROM c1;
.json null\
      true\
      1\
      "abc"\
      [1,2,7,4]\
      {"a":3,"b":2,"c":3, "2":7}

-- setting number properties on arrays potentially
-- grows the array, padding skipped elements with null
.testcase 4
UPDATE c1 SET c1["7"] = 9;
SELECT FROM c1;
.json null\
      true\
      1\
      "abc"\
      [1,2,7,4,null,null,null,9]\
      {"a":3,"b":2,"c":3, "2":7, "7":9}