大约有 47,000 项符合查询结果（耗时：0.0279秒） [XML]
Retrieve the maximum length of a VARCHAR column in SQL Server
...
Use the built-in functions for length and max on the description column:
SELECT MAX(LEN(DESC)) FROM table_name;
Note that if your table is very large, there can be performance issues.
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im...
Keeping it simple and how to do multiple CTE in a query
...s in one query, as well as reuse a CTE:
WITH cte1 AS
(
SELECT 1 AS id
),
cte2 AS
(
SELECT 2 AS id
)
SELECT *
FROM cte1
UNION ALL
SELECT *
FROM cte2
UNION ALL
SELECT *
FROM cte1
Note, however, that SQL Server may reevaluate t...
Best way to do multi-row insert in Oracle?
...acle:
insert into pager (PAG_ID,PAG_PARENT,PAG_NAME,PAG_ACTIVE)
select 8000,0,'Multi 8000',1 from dual
union all select 8001,0,'Multi 8001',1 from dual
The thing to remember here is to use the from dual statement.
(source)
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What is the most efficient/elegant way to parse a flat table into a tree?
...port recursive queries in standard syntax.
WITH RECURSIVE MyTree AS (
SELECT * FROM MyTable WHERE ParentId IS NULL
UNION ALL
SELECT m.* FROM MyTABLE AS m JOIN MyTree AS t ON m.ParentId = t.Id
)
SELECT * FROM MyTree;
I tested recursive queries in MySQL 8.0 in my presentation Recursive ...
Is there a better way to dynamically build an SQL WHERE clause than by using 1=1 at its beginning?
... {2}", clause, appender, condition);
}
Use it like this
string query = "SELECT * FROM Table1 {0}";
string whereClause = string.Empty;
if (condition 1)
whereClause = AddCondition(whereClause, "AND", "Col=1");
if (condition 2)
whereClause = AddCondition(whereClause, "AND", "Col2=2");
str...
Query grants for a table in postgres
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I already found it:
SELECT grantee, privilege_type
FROM information_schema.role_table_grants
WHERE table_name='mytable'
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Getting a 404 from WMSvc via MSDeploy.exe
...el > Programs and Features. Right-click "Microsoft Web Deploy 3.5" and select "Change". From the installer select "Change" and "IIS Deployment Handler" was available as an option (was disabled at first. Also "Configure for Non-Administrator Deployments" and "Management Service Delegation UI" w...
Check for changes to an SQL Server table?
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Take a look at the CHECKSUM command:
SELECT CHECKSUM_AGG(BINARY_CHECKSUM(*)) FROM sample_table WITH (NOLOCK);
That will return the same number each time it's run as long as the table contents haven't changed. See my post on this for more information:
CHECKSUM...
How do I see active SQL Server connections?
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when you have to filter for specific db selecting from sys.sysprocesses is better
– Iman
Dec 2 '13 at 4:29
2
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Parameterize an SQL IN clause
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Here's a quick-and-dirty technique I have used:
SELECT * FROM Tags
WHERE '|ruby|rails|scruffy|rubyonrails|'
LIKE '%|' + Name + '|%'
So here's the C# code:
string[] tags = new string[] { "ruby", "rails", "scruffy", "rubyonrails" };
const string cmdText = "select * from t...