/// <summary>
/// Executes a sql statement on a given table in local SQLCe database.
/// </summary>
/// <param name="tableName">The name of the table.</param>
/// <param name="sql">The SQL query to execute.</param>
/// <param name="parameters">The query parameters.</param>
/// <returns>The result of query.</returns>
protected virtual IList <JObject> ExecuteQuery(string tableName, string sql, IDictionary <string, object> parameters)
{
TableDefinition table = GetTable(tableName);
return(this.ExecuteQuery(table, sql, parameters));
}
private Task UpsertAsyncInternal(string tableName, IEnumerable <JObject> items, bool fromServer)
{
TableDefinition table = GetTable(tableName);
var first = items.FirstOrDefault();
if (first == null)
{
return(Task.FromResult(0));
}
// Get the columns which we want to map into the database.
var columns = new List <ColumnDefinition>();
foreach (var prop in first.Properties())
{
ColumnDefinition column;
// If the column is coming from the server we can just ignore it,
// otherwise, throw to alert the caller that they have passed an invalid column
if (!table.TryGetValue(prop.Name, out column) && !fromServer)
{
throw new InvalidOperationException(string.Format(Properties.Resources.SqlCeStore_ColumnNotDefined, prop.Name, tableName));
}
if (column != null)
{
columns.Add(column);
}
}
if (columns.Count == 0)
{
// no query to execute if there are no columns in the table
return(Task.FromResult(0));
}
var insertSqlBase = String.Format(
"INSERT INTO {0} ({1}) VALUES ",
SqlHelpers.FormatTableName(tableName),
String.Join(", ", columns.Select(c => c.Name).Select(SqlHelpers.FormatMember))
);
var updateSqlBase = String.Format("UPDATE {0} SET ", SqlHelpers.FormatTableName(tableName));
// Use int division to calculate how many times this record will fit into our parameter quota
int batchSize = MaxParametersPerUpsertQuery / columns.Count;
if (batchSize == 0)
{
throw new InvalidOperationException(string.Format(Properties.Resources.SqlCeStore_TooManyColumns, MaxParametersPerUpsertQuery));
}
foreach (var batch in items.Split(maxLength: batchSize))
{
StringBuilder sql = new StringBuilder();
var parameters = new Dictionary <string, object>();
foreach (JObject item in batch)
{
// there's no upsert in SQL CE so we'll settle if an 'If Not Exist, Insert' approach
if (!RowExists(SqlHelpers.FormatTableName(tableName),
item.GetValue(MobileServiceSystemColumns.Id, StringComparison.OrdinalIgnoreCase).ToString()))
{
sql = new StringBuilder(insertSqlBase);
AppendInsertValuesSql(sql, parameters, columns, item);
}
else
{
sql = new StringBuilder(updateSqlBase);
AppendUpdateValuesSql(sql, parameters, columns, item);
string updateCondition = string.Format(" WHERE {0} = '{1}'", MobileServiceSystemColumns.Id, item.GetValue(MobileServiceSystemColumns.Id, StringComparison.OrdinalIgnoreCase).ToString());
sql.Append(updateCondition);
}
if (parameters.Any())
{
this.ExecuteNonQuery(sql.ToString(), parameters);
}
}
}
return(Task.FromResult(0));
}