Function exec_prepared_stmt_columnar

lib-src/sqlite/shell.c:13203–13353

** Run a prepared statement and output the result in one of the ** table-oriented formats: MODE_Column, MODE_Markdown, MODE_Table, ** or MODE_Box. ** ** This is different from ordinary exec_prepared_stmt() in that ** it has to run the entire query and gather the results into memory ** first, in order to determine column widths, before providing ** any output. */

** any output.
*/
static void exec_prepared_stmt_columnar(
  ShellState *p,                        /* Pointer to ShellState */
  sqlite3_stmt *pStmt                   /* Statment to run */
){
  sqlite3_int64 nRow = 0;
  int nColumn = 0;
  char **azData = 0;
  sqlite3_int64 nAlloc = 0;
  const char *z;
  int rc;
  sqlite3_int64 i, nData;
  int j, nTotal, w, n;
  const char *colSep = 0;
  const char *rowSep = 0;

  rc = sqlite3_step(pStmt);
  if( rc!=SQLITE_ROW ) return;
  nColumn = sqlite3_column_count(pStmt);
  nAlloc = nColumn*4;
  if( nAlloc<=0 ) nAlloc = 1;
  azData = sqlite3_malloc64( nAlloc*sizeof(char*) );
  if( azData==0 ) shell_out_of_memory();
  for(i=0; i<nColumn; i++){
    azData[i] = strdup(sqlite3_column_name(pStmt,i));
  }
  do{
    if( (nRow+2)*nColumn >= nAlloc ){
      nAlloc *= 2;
      azData = sqlite3_realloc64(azData, nAlloc*sizeof(char*));
      if( azData==0 ) shell_out_of_memory();
    }
    nRow++;
    for(i=0; i<nColumn; i++){
      z = (const char*)sqlite3_column_text(pStmt,i);
      azData[nRow*nColumn + i] = z ? strdup(z) : 0;
    }
  }while( (rc = sqlite3_step(pStmt))==SQLITE_ROW );
  if( nColumn>p->nWidth ){
    p->colWidth = realloc(p->colWidth, nColumn*2*sizeof(int));
    if( p->colWidth==0 ) shell_out_of_memory();
    for(i=p->nWidth; i<nColumn; i++) p->colWidth[i] = 0;
    p->nWidth = nColumn;
    p->actualWidth = &p->colWidth[nColumn];
  }
  memset(p->actualWidth, 0, nColumn*sizeof(int));
  for(i=0; i<nColumn; i++){
    w = p->colWidth[i];
    if( w<0 ) w = -w;
    p->actualWidth[i] = w;
  }
  nTotal = nColumn*(nRow+1);
  for(i=0; i<nTotal; i++){
    z = azData[i];
    if( z==0 ) z = p->nullValue;
    n = strlenChar(z);
    j = i%nColumn;
    if( n>p->actualWidth[j] ) p->actualWidth[j] = n;
  }