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COALESCE Function in TSQL
Can someone explain how the COALESCE function in TSQL works? The syntax is as follows
7 Answers
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Using pg_dump to only get insert statements from one table within database
...ements from one specific table within a database using pg_dump in PostgreSQL.
4 Answers
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MySQL一次主从数据不一致的问题解决过程 - 数据库(内核) - 清泛网 - 专注C/...
...，虽然对主库的使用没有影响，但是那么大的数据量，对性能，网络影响有点大，数据丢失的应该很少
2 主库dump数据，锁库，然后同步，不好。 影响业务使用
3 percona-toolkit 中的工具来校验和同步，从介绍上来看是符合现在...
How do I use regex in a SQLite query?
I'd like to use a regular expression in sqlite, but I don't know how.
17 Answers
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SET NOCOUNT ON usage
...een using SET NOCOUNT ON forever, but marc_s pointed out the limitation of SQLDataAdapter in the other question.
– gbn
Oct 10 '09 at 12:26
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COUNT(*) vs. COUNT(1) vs. COUNT(pk): which is better? [duplicate]
...id
GROUP BY boss.id
But they cannot do that (COUNT(tableNameHere)) since SQL standard permits naming a field with the same name as its table name:
CREATE TABLE fruit -- ORM-friendly name
(
fruit_id int NOT NULL,
fruit varchar(50), /* same name as table name,
and let's say, someon...
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
... Having a problem with a similar situation in PhpMyAdmin over MySQL. In my case, the source and destination columns are in the same table, but record selection is based on the other table. The "SELECT" version of the query works, but the UPDTATE statement throws a syntax error at "FROM"...
What is an MDF file? [closed]
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SQL Server databases use two files - an MDF file, known as the primary database file, which contains the schema and data, and a LDF file, which contains the logs. See wikipedia. A database may also use secondary database file...
Oracle find a constraint
...in a table declaration. Or indeed a primary or unique key. For example:
SQL> create table t23 (id number not null primary key)
2 /
Table created.
SQL> select constraint_name, constraint_type
2 from user_constraints
3 where table_name = 'T23'
4 /
CONSTRAINT_NAME ...
How to switch databases in psql?
In MySQL , I used use database_name;
12 Answers
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