private static IReadOnlyCollection <string> GetPagingSql(SelectConfiguration selectConfiguration)
{
var result = new List <string>
{
"COUNT(1) OVER() ROW_COUNT, ",
$@"{GetSortSql(selectConfiguration)}
OFFSET {(selectConfiguration.PageNumber - 1) * selectConfiguration.PageSize} ROWS
FETCH NEXT {selectConfiguration.PageSize} ROWS ONLY;"
};
return(result);
}
private static string GetSortSql(SelectConfiguration selectConfiguration)
{
if (selectConfiguration?.SortColumns?.Any() ?? false)
{
var orderByColumnsBuilder = new StringBuilder();
selectConfiguration.SortColumns.ForEach(s =>
{
orderByColumnsBuilder.Append($"{s.Name} {s.SortOrder}, ");
});
return(orderByColumnsBuilder.ToString().TrimEnd(new char[] { ',', ' ' }));
}
return($"ORDER BY {selectConfiguration?.KeyColumnName} ");
}
private static string GetTableRelationships(SelectConfiguration selectConfiguration)
{
if (!(selectConfiguration?.Relationships?.Any() ?? false))
{
return(string.Empty);
}
var result = new StringBuilder();
selectConfiguration.Relationships.ForEach(t =>
{
result.Append($"{t.JoinType} {t.Table2Name} {(string.IsNullOrEmpty(t.Table2AsName)? string.Empty : "AS " + t.Table2AsName)} ON {t.Table1Name}.{t.Table1ColumnName} = {(string.IsNullOrEmpty(t.Table2AsName) ? t.Table2Name : t.Table2AsName)}.{t.Table2ColumnName} " + Environment.NewLine);
});
return(result.ToString());
}
private static string GetTableColumns(SelectConfiguration selectConfiguration)
{
if (!(selectConfiguration?.Columns?.Any() ?? false))
{
return(string.Empty);
}
var result = new StringBuilder();
selectConfiguration.Columns.ForEach(t =>
{
result.Append(
$", {t.TableName}.{t.Name}{(string.IsNullOrEmpty(t.AsName) ? string.Empty : " AS " + t.AsName)} ");
});
return(result.ToString().TrimStart(new char[] { ',' }));
}
public string GetSelectQuery(SelectConfiguration selectConfiguration)
{
if (selectConfiguration == null)
{
throw new ArgumentException("Invalid table parameter values supplied");
}
if (string.IsNullOrEmpty(selectConfiguration.KeyColumnName))
{
throw new ArgumentException("Key column is required");
}
if (string.IsNullOrEmpty(selectConfiguration.MainTableName))
{
throw new ArgumentException("Main table name is required");
}
if (selectConfiguration.Columns == null || !selectConfiguration.Columns.Any())
{
throw new ArgumentException("Atleast one column is required");
}
if (selectConfiguration?.IsPaging ?? false)
{
if (selectConfiguration.PageNumber <= 0)
{
throw new ArgumentException("Invalid pagenumber is supplied");
}
if (selectConfiguration.PageSize <= 0)
{
throw new ArgumentException("Invalid pagesize is supplied");
}
var pagingSqlArray = GetPagingSql(selectConfiguration);
return($@"SELECT {pagingSqlArray.First()}
{GetTableColumns(selectConfiguration)} FROM
{selectConfiguration.MainTableName}
{GetTableRelationships(selectConfiguration)}
{GetWhereCondition(selectConfiguration.WhereConditions)}
{pagingSqlArray.ElementAt(1)}");
}
return($"SELECT {GetTableColumns(selectConfiguration)} FROM {selectConfiguration.MainTableName} {GetTableRelationships(selectConfiguration)}");
}