如何编写mysql查询以准确返回4行

我想要显示表格中的4行。 我有使用以下查询

SELECT field_name FROM tbl_name WHERE col_name ='value'LIMIT 4;

该表包含4个以上的值意味着它能够完美显示前4行。 但它少于4行意味着我需要结果为以下结果

它仅显示2行意味着

FIELD_NAME
ROW1
2行
2行
ROW1

它仅显示3行意味着

FIELD_NAME
ROW1
2行
ROW3
ROW1

我怎样才能得到这个结果？

---

像这样尝试

Select * from (

select * from tbl_name WHERE col_name = 'value' LIMIT 4
union all 
select * from tbl_name WHERE col_name = 'value' LIMIT 4
union all
select * from tbl_name WHERE col_name = 'value' LIMIT 4
union all
select * from tbl_name WHERE col_name = 'value' LIMIT 4) as table1   LIMIT 4

---

不是一个很好的解决方案，但它应该可以工作：您可以使用UNION ALL重复查询4次，并限制为4个结果：

SELECT * FROM (
    SELECT field_name FROM tbl_name WHERE col_name = 'value' LIMIT 4;
    UNION ALL
    SELECT field_name FROM tbl_name WHERE col_name = 'value' LIMIT 4;
    UNION ALL
    SELECT field_name FROM tbl_name WHERE col_name = 'value' LIMIT 4;
    UNION ALL
    SELECT field_name FROM tbl_name WHERE col_name = 'value' LIMIT 4;
) a LIMIT 4

---

SELECT Column_Name
FROM (
SELECT Column_Name, ROW_NUMBER() OVER (ORDER BY Column_Name) AS RowNum
FROM [dbo].[AttendanceLog]
) AS MyDerivedTable
 WHERE MyDerivedTable.RowNum BETWEEN 1 and 4

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