/// <summary>
/// 加载每个表的所有列
/// </summary>
/// <param name="database"></param>
protected override void LoadAllColumns(Database database)
{
foreach (Table table in database.Tables)
{
using (var columnsReader = this.Db.QueryDataReader(@"
SELECT C.COLUMN_NAME, C.IS_NULLABLE, C.DATA_TYPE, C.CHARACTER_MAXIMUM_LENGTH
FROM INFORMATION_SCHEMA.COLUMNS C
WHERE C.TABLE_NAME = {0}
", table.Name))
{
while (columnsReader.Read())
{
string columnName = columnsReader["COLUMN_NAME"].ToString();
string sqlType = columnsReader["DATA_TYPE"].ToString();
string length = null;
var lengthObj = columnsReader["CHARACTER_MAXIMUM_LENGTH"];
if (lengthObj != null && !DBNull.Value.Equals(lengthObj) && lengthObj.ToString() != "-1")
{
length = lengthObj.ToString();
}
DbType dbType = SqlDbTypeHelper.ConvertFromSQLTypeString(sqlType);
Column column = new Column(dbType, length, columnName, table);
column.IsRequired = string.Compare(columnsReader["IS_NULLABLE"].ToString(), "no", true) == 0;
table.Columns.Add(column);
}
table.SortColumns();
}
}
this.LoadIsIdentity(database);
}
/// <summary>
/// 加载每个表的所有列
/// </summary>
/// <param name="database"></param>
protected override void LoadAllColumns(Database database)
{
//用一句 Sql 将所有的表的所有字段都一次性查询出来。
var sql = new StringBuilder(
@"SELECT TABLE_NAME, COLUMN_NAME, IS_NULLABLE, DATA_TYPE, CHARACTER_MAXIMUM_LENGTH
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME IN (");
sql.Append(string.Join(",", database.Tables.Select(t => "'" + t.Name + "'")));
sql.Append(@")
ORDER BY TABLE_NAME");
using (var columnsReader = this.Db.QueryDataReader(sql.ToString()))
{
Table currentTable = null;//当前正在处理的表。（放在循环外，有缓存的作用。）
while (columnsReader.Read())
{
//找到该列所对应的表。
var tableName = columnsReader["TABLE_NAME"].ToString();
if (currentTable == null || !currentTable.Name.EqualsIgnoreCase(tableName))
{
currentTable = database.FindTable(tableName);
}
string columnName = columnsReader["COLUMN_NAME"].ToString();
string sqlType = columnsReader["DATA_TYPE"].ToString();
//不再读取 Length
//string length = null;
//var lengthObj = columnsReader["CHARACTER_MAXIMUM_LENGTH"];
//if (lengthObj != null && !DBNull.Value.Equals(lengthObj) && lengthObj.ToString() != "-1")
//{
// length = lengthObj.ToString();
//}
DbType dbType = SqlDbTypeHelper.ConvertFromSQLTypeString(sqlType);
Column column = new Column(columnName, dbType, null, currentTable);
column.IsRequired = "NO".EqualsIgnoreCase(columnsReader["IS_NULLABLE"].ToString());
currentTable.Columns.Add(column);
}
}
}
protected override string ConvertToTypeString(DbType dataType, string length)
{
return(SqlDbTypeHelper.ConvertToSQLTypeString(dataType, length));
}
