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Declaring a default constraint when creating a table
I am creating a new table in Microsoft SQL server 2000 by writing the code instead of using the GUI, I am trying to learn how to do it "the manual way".
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Why is iterating through a large Django QuerySet consuming massive amounts of memory?
...hanks for the great answer, @eternicode. In the end we dropped down to raw SQL for the desired database-level iteration.
– davidchambers
Aug 13 '11 at 21:15
2
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Condition within JOIN or WHERE
...eports joining 5-6 tables on few millions records. Perf improves by 30% - sql server 2012
– Shahdat
Oct 6 '16 at 16:33
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LINQPad [extension] methods [closed]
...teXhtmlWriter - creates a text writer that uses LINQPad's Dump() formatter
SqlOutputWriter - returns the text writer that writes to the SQL output window
GetMyQueries, GetSamples - returns a collection of objects representing your saved queries / samples (for an example, execute a search using Edit ...
Nginx缓存解决方案：SRCache - 更多技术 - 清泛网 - 专注C/C++及内核技术
...求，可以用xss-nginx-module来搞定。
关于激活SRCache前后的性能对比，视环境的不同会有所差异，不过绝对是数量级的提升，更重要的是这一切对业务层完全透明，别愣着了，快试试吧！
Nginx SRCache 缓存
how perform grep operation on all files in a directory
...use then you can really see what files it's operating on:
find . -name "*.sql" -exec grep -H "slow" {} \;
Note, the -H is mac-specific, it shows the filename in the results.
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Specifying an Index (Non-Unique Key) Using JPA
...tHub. Java, Kotlin, Android): Annotation io.requery.Index;
Exposed (Kotlin SQL Library): org.jetbrains.exposed.sql.Index, org.jetbrains.exposed.sql.Table#index(). Example:
object Persons : IdTable() {
val code = varchar("code", 50).index()
}
= ORM for Android =
♥ ActiveAndroid: Annotat...
Only read selected columns
... fread("data.txt", select = c(1:7), data.table = FALSE)
2) With read.csv.sql from the sqldf-package:
Another alternative is the read.csv.sql function from the sqldf package:
library(sqldf)
dat <- read.csv.sql("data.txt",
sql = "select Year,Jan,Feb,Mar,Apr,May,Jun from file...
Why do you need to create a cursor when querying a sqlite database?
I'm completely new to Python's sqlite3 module (and SQL in general for that matter), and this just completely stumps me. The abundant lack of descriptions of cursor objects (rather, their necessity) also seems odd.
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How to use Oracle ORDER BY and ROWNUM correctly?
I am having a hard time converting stored procedures from SQL Server to Oracle to have our product compatible with it.
4 An...