/// <summary>
/// 获取字段名
/// </summary>
/// <param name="type"></param>
/// <param name="csharpName"></param>
/// <returns></returns>
protected string GetColumnName(Type type, string csharpName)
{
var columns = DbMetaCache.GetColumns(type);
return(columns.Where(a => a.CsharpName == csharpName)
.FirstOrDefault().ColumnName);
}
private string ResovleCount()
{
var table = DbMetaCache.GetTable(typeof(T)).TableName;
var column = "COUNT(1)";
var where = ResolveWhere();
var group = ResolveGroup();
if (group.Length > 0)
{
column = group.Remove(0, 10);
}
else if (_countExpression != null)
{
column = new SelectExpressionResovle(_countExpression).Resovle();
}
var sql = $"SELECT {column} FROM {table}{where}{group}";
if (group.Length > 0)
{
sql = $"SELECT COUNT(1) FROM ({sql}) as t";
return(sql);
}
return(sql);
}
private string ResovleDelete()
{
var table = DbMetaCache.GetTable(typeof(T)).TableName;
var where = ResolveWhere();
var sql = $"DELETE FROM {table}{where}";
return(sql);
}
private string ResovleExists()
{
var table = DbMetaCache.GetTable(typeof(T)).TableName;
var where = ResolveWhere();
var group = ResolveGroup();
var having = ResolveHaving();
var sql = $"SELECT 1 WHERE EXISTS(SELECT 1 FROM {table}{where}{group}{having})";
return(sql);
}
private string ResolveColumns()
{
if (_selectExpression == null)
{
var filters = new GroupExpressionResovle(_filterExpression)
.Resovle().Split(',');
var columns = DbMetaCache.GetColumns(typeof(T))
.Where(a => !filters.Contains(a.ColumnName) && !a.IsNotMapped)
.Select(s => s.ColumnName != s.CsharpName ? $"{s.ColumnName} AS {s.CsharpName}" : s.CsharpName);
return(string.Join(",", columns));
}
else
{
return(new SelectExpressionResovle(_selectExpression).Resovle());
}
}
private string ResovleInsert(bool identity)
{
var table = DbMetaCache.GetTable(typeof(T)).TableName;
var filters = new GroupExpressionResovle(_filterExpression).Resovle().Split(',');
var columns = DbMetaCache.GetColumns(typeof(T));
var intcolumns = columns
.Where(a => !filters.Contains(a.ColumnName) && !a.IsNotMapped && !a.IsIdentity);
var columnNames = string.Join(",", intcolumns.Select(s => s.ColumnName));
var parameterNames = string.Join(",", intcolumns.Select(s => $"@{s.CsharpName}"));
var sql = $"INSERT INTO {table}({columnNames}) VALUES ({parameterNames})";
if (identity)
{
sql = $"{sql};SELECT @@IDENTITY";
}
return(sql);
}
private string ResolveSelect()
{
var table = DbMetaCache.GetTable(typeof(T)).TableName;
var column = ResolveColumns();
var where = ResolveWhere();
var group = ResolveGroup();
var having = ResolveHaving();
var order = ResolveOrder();
string sql;
if (_context.DbContextType == DbContextType.SqlServer)
{
if (_lockname != string.Empty)
{
_lockname = $" WITH({_lockname})";
}
if (_page.Index == 0)
{
sql = $"SELECT TOP {_page.Count} {column} FROM {table}{_lockname}{where}{group}{having}{order}";
}
else if (_page.Index > 0)
{
if (order == string.Empty)
{
order = " ORDER BY (SELECT 1)";
}
var limit = $" OFFSET {_page.Index} ROWS FETCH NEXT {_page.Count} ROWS ONLY";
sql = $"SELECT {column} FROM {_lockname}{table}{where}{group}{having}{order}{limit}";
}
else
{
sql = $"SELECT {column} FROM {_lockname}{table}{where}{group}{having}{order}";
}
}
else
{
var limit = _page.Index > 0 || _page.Count > 0 ? $" LIMIT {_page.Index},{_page.Count}" : string.Empty;
sql = $"SELECT {column} FROM {table}{where}{group}{having}{order}{limit}{_lockname}";
}
return(sql);
}
private string ResolveUpdate()
{
var table = DbMetaCache.GetTable(typeof(T)).TableName;
var builder = new StringBuilder();
if (_setExpressions.Count > 0)
{
var where = ResolveWhere();
foreach (var item in _setExpressions)
{
var column = new BooleanExpressionResovle(item.Column).Resovle();
var expression = new BooleanExpressionResovle(item.Expression, _parameters).Resovle();
builder.Append($"{column} = {expression},");
}
var sql = $"UPDATE {table} SET {builder.ToString().Trim(',')}{where}";
return(sql);
}
else
{
var filters = new GroupExpressionResovle(_filterExpression).Resovle().Split(',');
var where = ResolveWhere();
var columns = DbMetaCache.GetColumns(typeof(T));
var updcolumns = columns
.Where(a => !filters.Contains(a.ColumnName))
.Where(a => !a.IsIdentity && !a.IsPrimaryKey && !a.IsNotMapped)
.Select(s => $"{s.ColumnName} = @{s.CsharpName}");
if (string.IsNullOrEmpty(where))
{
var primaryKey = columns.Where(a => a.IsPrimaryKey).FirstOrDefault()
?? columns.First();
where = $" WHERE {primaryKey.ColumnName} = @{primaryKey.CsharpName}";
}
var sql = $"UPDATE {table} SET {string.Join(",", updcolumns)}{where}";
return(sql);
}
}
