大约有 5,881 项符合查询结果（耗时：0.0179秒） [XML]
Checking if a SQL Server login already exists
...ction. Attacker can pass a @loginName like x] with password ''y'';\r\ndrop table foo;\r\n
– Remus Rusanu
Sep 4 '09 at 14:47
2
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NHibernate vs LINQ to SQL
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LINQ to SQL forces you to use the table-per-class pattern. The benefits of using this pattern are that it's quick and easy to implement and it takes very little effort to get your domain running based on an existing database structure. For simple applicatio...
NULL values inside NOT IN clause
...s one using a not in where constraint and the other a left join . The table in the not in constraint had one null value (bad data) which caused that query to return a count of 0 records. I sort of understand why but I could use some help fully grasping the concept.
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Difference between a theta join, equijoin and natural join
...uijoin will also remove the equality column if they have same name in both tables.
– Vishal R
Nov 13 '14 at 3:42
1
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read.csv warning 'EOF within quoted string' prevents complete reading of file
...ng 403 back with read.csv(). Adding quote = "" got me up to 410 rows. read.table() does no better. I wonder what else can be tried...
– Hack-R
Aug 21 '14 at 15:12
2
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SQL Server reports 'Invalid column name', but the column is present and the query works through mana
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I suspect that you have two tables with the same name. One is owned by the schema 'dbo' (dbo.PerfDiag), and the other is owned by the default schema of the account used to connect to SQL Server (something like userid.PerfDiag).
When you have an unquali...
For loop example in MySQL
...
drop table if exists foo;
create table foo
(
id int unsigned not null auto_increment primary key,
val smallint unsigned not null default 0
)
engine=innodb;
drop procedure if exists load_foo_test_data;
delimiter #
create procedur...
IN clause and placeholders
...", "name2" }; // do whatever is needed first
String query = "SELECT * FROM table"
+ " WHERE name IN (" + makePlaceholders(names.length) + ")";
Cursor cursor = mDb.rawQuery(query, names);
Just make sure to pass exactly as many values as places. The default maximum limit of host parameters in SQ...
How to prepend a string to a column value in MySQL?
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UPDATE tablename SET fieldname = CONCAT("test", fieldname) [WHERE ...]
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foll...
Is there any boolean type in Oracle databases?
...efer char(1) because it uses less space. You can check it this way: create table testbool (boolc char(1), booln number(1)); insert into testbool values ('Y', 1 ); select dump(boolc), dump(booln) from testbool; That CHAR is stored: Typ=96 Len=1: 89 and that NUMBER: Typ=2 Len=2: 193,2 At least in 12c...