/// <summary>
/// 查询返回第一行第一列字段的值
/// </summary>
/// <typeparam name="TResult">接受查询结果类型</typeparam>
/// <param name="field">查询的字段</param>
/// <returns></returns>
public TResult ToScalar <TResult>(string field)
{
Fields.Clear();
Fields.Add(field);
string cmdText = ToString();
object result = null;
if (Master)
{
result = PgSqlHelper.ExecuteScalar(CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, this.ParamList.ToArray());
}
else
{
result = PgSqlHelper.ExecuteScalarSlave(CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, this.ParamList.ToArray());
}
return((TResult)result);
}
/// <summary>
/// 执行 Insert 语句并返回 Insert 后的结果,该方法仅提供在主数据源上执行，无法对从库源执行此方法
/// </summary>
/// <param name="cmdText">Insert SQL 语句</param>
/// <returns></returns>
protected T InsertOnReader(string cmdText)
{
this.commandtext = cmdText;
T restult = default(T);
PgSqlHelper.ExecuteDataReader(dr =>
{
restult = DynamicBuilder <T> .CreateBuilder(dr).Build(dr);
}, CommandType.Text, this.commandtext, this.ParamList.ToArray());
return(restult);
}
/// <summary>
/// 执行查询并返回结果集
/// </summary>
/// <typeparam name="TResult">接受查询结果对象类型</typeparam>
/// <returns></returns>
public List <TResult> ExecuteReader <TResult>(string cmdText)
{
List <TResult> list = new List <TResult>();
DynamicBuilder <TResult> builder = null;
void action(DbDataReader dr)
{
TResult obj = default(TResult);
Type objType = typeof(TResult);
bool isTuple = objType.Namespace == "System" && objType.Name.StartsWith("ValueTuple`");
if (isTuple)
{
int columnIndex = -1;
obj = (TResult)GetValueTuple(objType, dr, ref columnIndex);
}
else if (IsValueType(objType))
{
obj = (TResult)GetValueType(objType, dr);
}
else if (objType.Namespace.StartsWith("Newtonsoft"))
{
obj = (TResult)GetJToken(dr);
}
else
{
if (builder == null)
{
builder = DynamicBuilder <TResult> .CreateBuilder(dr);
}
obj = builder.Build(dr);
}
list.Add(obj);
}
if (PgSqlHelper.InstanceSlave != null && !Master)
{
PgSqlHelper.ExecuteDataReaderSlave(action, CommandType.Text, cmdText, this.ParamList.ToArray());
}
else
{
PgSqlHelper.ExecuteDataReader(action, CommandType.Text, cmdText, this.ParamList.ToArray());
}
return(list);
}
/// <summary>
/// 查询返回第一行第一列字段的值
/// </summary>
/// <typeparam name="TResult">接受查询结果类型</typeparam>
/// <param name="field">查询的字段</param>
/// <returns></returns>
public TResult ToScalar <TResult>(string field)
{
Fields.Clear();
Fields.Add(field);
string cmdText = ToString();
object _val = null;
if (PgSqlHelper.InstanceSlave != null && !this.Master)
{
_val = PgSqlHelper.ExecuteScalarSlave(CommandType.Text, cmdText, this.ParamList.ToArray());
}
else
{
_val = PgSqlHelper.ExecuteScalar(CommandType.Text, cmdText, this.ParamList.ToArray());
}
return((TResult)_val);
}
/// <summary>
/// 执行查询，并返回受影响的行数
/// </summary>
/// <param name="cmdText"></param>
/// <returns></returns>
public int ExecuteNonQuery(string cmdText, DbParameter[] parameters)
{
var affrows = 0;
try
{
affrows = PgSqlHelper.ExecuteNonQuery(CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, parameters);
}
finally
{
this.Clear();
}
return(affrows);
}
/// <summary>
/// 执行查询并返回结果集
/// </summary>
/// <typeparam name="TResult">接受查询结果对象类型</typeparam>
/// <returns></returns>
public List <TResult> ExecuteReader <TResult>(string cmdText)
{
List <TResult> list = new List <TResult>();
DynamicBuilder <TResult> builder = null;
Type objType = typeof(TResult);
try
{
if (Master)
{
PgSqlHelper.ExecuteDataReader(dr =>
{
var obj = ReadObj <TResult>(ref builder, dr, objType);
list.Add(obj);
}
, CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, this.ParamList.ToArray());
}
else
{
PgSqlHelper.ExecuteDataReaderSlave(dr =>
{
var obj = ReadObj <TResult>(ref builder, dr, objType);
list.Add(obj);
}
, CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, this.ParamList.ToArray());
}
}
finally
{
this.Clear();
}
return(list);
}
/// <summary>
/// 查询返回第一行第一列字段的值
/// </summary>
/// <typeparam name="TResult">接受查询结果类型</typeparam>
/// <param name="field">查询的字段</param>
/// <returns></returns>
public TResult ToScalar <TResult>(string field)
{
if (!string.IsNullOrEmpty(GroupByText))
{
throw new ArgumentException("聚合查询不允许使用 GROUP BY 条件！");
}
Fields.Clear();
Fields.Add(field);
string cmdText = ToSQL();
object result = null;
if (Master)
{
result = PgSqlHelper.ExecuteScalar(CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, this.ParamList.ToArray());
}
else
{
result = PgSqlHelper.ExecuteScalarSlave(CommandType.Text, cmdText, command =>
{
this.Command = command;
this.Connection = command?.Connection;
}, this.ParamList.ToArray());
}
// Clear();
if (result == null)
{
return(default(TResult));
}
else
{
return((TResult)result);
}
}
/// <summary> /// 执行查询，并返回受影响的行数 /// </summary> /// <param name="cmdText"></param> /// <returns></returns> public int ExecuteNonQuery(string cmdText) => PgSqlHelper.ExecuteNonQuery(CommandType.Text, cmdText, ParamList.ToArray());
