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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...
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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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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Entity Attribute Value Database vs. strict Relational Model Ecommerce
...complex code required to validate simple data types
Con: much more complex SQL for simple
reports
Con: complex reports can become almost
impossible
Con: poor performance for large data sets
Option 2, Modelling each entity separately:
Con: more time required to gather
requirements and design
Con:...
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...
Pythonic way to create a long multi-line string
...essee example code show how NOT to do it correctly (they're invitations to SQL attacks). See also: dev.mysql.com/doc/connector-python/en/…
– Scott Prive
Oct 8 '16 at 17:29
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How do you truncate all tables in a database using TSQL?
...
For SQL 2005,
EXEC sp_MSForEachTable 'TRUNCATE TABLE ?'
Couple more links for 2000 and 2005/2008..
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What is the difference between varchar and varchar2 in Oracle?
...r VARCHAR2. It is NOT a SYNONYM which is an actual object type in Oracle.
SQL> select substr(banner,1,80) from v$version where rownum=1;
Oracle Database 12c Enterprise Edition Release 12.2.0.1.0 - 64bit Production
SQL> create table test (my_char varchar(20));
Table created.
SQL> desc...
Under what circumstances is an SqlConnection automatically enlisted in an ambient TransactionScope T
What does it mean for an SqlConnection to be "enlisted" in a transaction? Does it simply mean that commands I execute on the connection will participate in the transaction?
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