本文整理汇总了C#中System.Data.Common.DbConnection.ExecuteScalar方法的典型用法代码示例。如果您正苦于以下问题：C# DbConnection.ExecuteScalar方法的具体用法？C# DbConnection.ExecuteScalar怎么用？C# DbConnection.ExecuteScalar使用的例子？那么恭喜您, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类System.Data.Common.DbConnection的用法示例。
在下文中一共展示了DbConnection.ExecuteScalar方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C#代码示例。
示例1: GetCount
static int GetCount(string tableName, DbConnection connection)
{
try {
return connection.ExecuteScalar<int>("SELECT COUNT(*) FROM [" + tableName.Replace("]", "]]") + "]");
} catch { return -1; }
}示例2: FillExternalSources
private void FillExternalSources(DbConnection conn, IDatabaseFactory factory, IShellContext context)
{
if (!_externalSources.Any()) return;
var sw = new StringWriter();
var so = new ConnectionSqlOutputStream(conn, null, factory.CreateDialect());
var dmp = factory.CreateDumper(so, new SqlFormatProperties());
foreach (var exSource in _externalSources)
{
var tbl = new TableInfo(null) { FullName = exSource.ExternalDataName };
foreach (var col in exSource.Dbsh.Columns)
{
tbl.Columns.Add(new ColumnInfo(tbl)
{
Name = col.Name,
DataType = col.DataType ?? "nvarchar(500)",
CommonType = DbTypeBase.ParseType(col.DataType ?? "nvarchar(500)"),
});
}
dmp.CreateTable(tbl);
var filterModel = FilterJoinSqlModel.Create(exSource, SourceGraphModel, factory);
var copyTable = new DbShell.Core.CopyTable
{
Source = filterModel?.DataSource ?? exSource.Dbsh.DataSource,
Target = new DbShell.Core.Table
{
Name = exSource.ExternalDataName.Name,
StructureOverride = tbl,
},
AllowBulkCopy = _model.AllowBulkCopy,
};
var runnable = (IRunnable)copyTable;
runnable.Run(context);
if (exSource.Dbsh.OnExternalFilledAssertion != null)
{
string value = conn.ExecuteScalar(exSource.Dbsh.OnExternalFilledAssertion.Replace("${TABLE}", exSource.ExternalDataName.Name))?.ToString();
if (value != exSource.Dbsh.OnExternalFilledRequiredValue)
{
throw new Exception($"DBSH-00000 OnExternalFilledAssertion failed, source={exSource.SqlAlias}, required={exSource.Dbsh.OnExternalFilledRequiredValue}, actual={value}, query={exSource.Dbsh.OnExternalFilledAssertion}");
}
}
}
}