function initializeProjection()

in jones-mysql/impl/MySQLConnection.js [634:759]
102 lines of code
16 McCabe index (conditional complexity)

function initializeProjection(projection) {
  var mysql = {};
  projection.mysql = mysql;
  var i, j;
  var sector, sectorName;
  var parentSectorName;
  var select, from, on, alias, order;
  var thisOn, otherOn, and;

  var selectDelimiter, fromDelimiter, orderDelimiter;
  var columnName;
  var joinType, joinIndex;
  var offset;
  var keyField, nonKeyField;

  // create the sql query for the find method.
  select = 'SELECT ';
  from = ' FROM ';
  order = '';
  selectDelimiter = '';
  fromDelimiter = '';
  orderDelimiter = '';
  alias = 0;
  offset = 0;

  // always order by first table primary key to avoid duplicates in scan results

  for (i = 0; i < projection.sectors.length; ++i) {
    sector = projection.sectors[i];
    udebug.log_detail('initializeProjection for sector\n', sector);
    // offset of each sector into column in row
    sector.offset = offset;
    offset += sector.keyFields.length + sector.nonKeyFields.length;

    // set up the table names
    sector.tableName = sector.tableHandler.dbTable.database + '.' + sector.tableHandler.dbTable.name;
    sectorName = 't' + i;
    parentSectorName = 't' + sector.parentSectorIndex;
    joinType = '';
    on = '';
    if (sector.parentFieldMapping && i > 0) {
      if (sector.parentFieldMapping.toMany && sector.parentFieldMapping.manyTo) {
        // join table mapping
        // create a join table reference based on current table name
        // join tables are "between" tables that are joined for many-to-many relationships
        // ... t1 LEFT OUTER JOIN customerdiscount AS t15 on [t1.k = t15.k and...] 
        //     LEFT OUTER JOIN discount AS t2 on [t15.k = t2.k and ...]
        sector.joinTableName = sector.joinTableHandler.dbTable.database + '.' + sector.joinTableHandler.dbTable.name;
        sector.joinTableAlias = sectorName + 'JOIN';
        udebug.log_detail('initializeProjection join table handling for', sector.joinTableName, 'AS', sector.joinTableAlias,
            'thisForeignKey.columnNames', sector.parentFieldMapping.thisForeignKey.columnNames,
            'otherForeignKey.columnNames', sector.parentFieldMapping.otherForeignKey.columnNames);
        // generate the join from the previous domain table to the join table
        joinType = ' LEFT OUTER JOIN ';
        thisOn = ' ON ';
        and = '';
        for (joinIndex = 0; joinIndex < sector.parentFieldMapping.thisForeignKey.columnNames.length; ++joinIndex) {
          thisOn += and + parentSectorName + '.' + sector.parentFieldMapping.thisForeignKey.targetColumnNames[joinIndex] + ' = ' +
              sector.joinTableAlias + '.' + sector.parentFieldMapping.thisForeignKey.columnNames[joinIndex];
          and = ' AND ';
        }
        from += fromDelimiter + joinType + sector.joinTableName + ' AS ' + sector.joinTableAlias + thisOn;

        // generate the join from the join table to this domain table
        otherOn = ' ON ';
        and = '';
        for (joinIndex = 0; joinIndex < sector.parentFieldMapping.otherForeignKey.columnNames.length; ++joinIndex) {
          otherOn += and + sector.joinTableAlias + '.' + sector.parentFieldMapping.otherForeignKey.columnNames[joinIndex] + ' = ' +
          sectorName + '.' + sector.parentFieldMapping.otherForeignKey.targetColumnNames[joinIndex];
          and = ' AND ';
        }
        from += fromDelimiter + joinType + sector.tableName + ' AS ' + sectorName + otherOn;

      } else {
        // foreign key mapping for one-to-one, one-to-many, and many-to-one relationships
        joinType = ' LEFT OUTER JOIN ';
        on = ' ON ';
        and = '';
        for (joinIndex = 0; joinIndex < sector.thisJoinColumns.length; ++joinIndex) {
          on += and + parentSectorName + '.' + sector.otherJoinColumns[joinIndex] + ' = ' +
                sectorName + '.' + sector.thisJoinColumns[joinIndex];
          and = ' AND ';
        }
        from += fromDelimiter + joinType + sector.tableName + ' AS ' + sectorName + on;
      }
    } else {
      // first table is always t0
      from += sector.tableName + ' AS ' + sectorName;
      fromDelimiter = ' ';
    }
    if (i == 0 || sector.parentFieldMapping.toMany) {
      // order by key columns that can have multiple values (toMany relationships and first sector)
      for (j = 0; j < sector.keyFields.length; ++j) {
        keyField = sector.keyFields[j];
        columnName = keyField.columnName;
        order += orderDelimiter + sectorName + '.' + columnName;
        orderDelimiter = ', ';
      }
    }
    // add key column names to SELECT clause
    for (j = 0; j < sector.keyFields.length; ++j) {
      keyField = sector.keyFields[j];
      columnName = keyField.columnName;
      select += selectDelimiter + sectorName + '.' + columnName + ' AS \'' + alias++ + '\'';
      selectDelimiter = ', ';
    }
    // add non-key column names to SELECT clause
    for (j = 0; j < sector.nonKeyFields.length; ++j) {
      nonKeyField = sector.nonKeyFields[j];
      columnName = nonKeyField.columnName;
      select += selectDelimiter + sectorName + '.' + columnName + ' AS \'' + alias++ + '\'';
      selectDelimiter = ', ';
    }
  }
  mysql.select = select;
  mysql.from = from;
  mysql.sectors = projection.sectors;
  if (order) {
    mysql.order = ' ORDER BY ' + order;
  } else {
    mysql.order = '';
  }
  // mark this as having been processed
  projection.mysql.id = projection.id;
  if (udebug.is_debug()) {udebug.log_detail('initializeProjection', select, from);}
}