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Importing a CSV file into a sqlite3 database table using Python
...nge to 'sqlite:///your_filename.db'
cur = con.cursor()
cur.execute("CREATE TABLE t (col1, col2);") # use your column names here
with open('data.csv','r') as fin: # `with` statement available in 2.5+
# csv.DictReader uses first line in file for column headings by default
dr = csv.DictReader(...
MySQL - UPDATE query based on SELECT Query
I need to check (from the same table) if there is an association between two events based on date-time.
11 Answers
...
Foreign key constraints: When to use ON UPDATE and ON DELETE
...eign key constraints are quite advanced.
We'll take an example, a company table with a user table containing people from theses company
CREATE TABLE COMPANY (
company_id INT NOT NULL,
company_name VARCHAR(50),
PRIMARY KEY (company_id)
) ENGINE=INNODB;
CREATE TABLE USER (
user_...
What is the most efficient way to store tags in a database?
... items. This implies to me that you'll quite possibly need an intermediary table to overcome the many-to-many obstacle.
Something like:
Table: Items
Columns: Item_ID, Item_Title, Content
Table: Tags
Columns: Tag_ID, Tag_Title
Table: Items_Tags
Columns: Item_ID, Tag_ID
It might be that your web...
How to pass an array into a SQL Server stored procedure
...our database, create the following two objects:
CREATE TYPE dbo.IDList
AS TABLE
(
ID INT
);
GO
CREATE PROCEDURE dbo.DoSomethingWithEmployees
@List AS dbo.IDList READONLY
AS
BEGIN
SET NOCOUNT ON;
SELECT ID FROM @List;
END
GO
Now in your C# code:
// Obtain your list of ids to send, this...
Python SQL query string formatting
...Code Sample:
sql = ("SELECT field1, field2, field3, field4 "
"FROM table "
"WHERE condition1=1 "
"AND condition2=2;")
Works as well with f-strings:
fields = "field1, field2, field3, field4"
table = "table"
conditions = "condition1=1 AND condition2=2"
sql = (f"SELECT {fields...
What is the fastest way to compute sin and cos together?
...are supported on processor level, I expect them to be way much faster than table lookups.
Edit:
Wikipedia suggests that FSINCOS was added at 387 processors, so you can hardly find a processor which doesn't support it.
Edit:
Intel's documentation states that FSINCOS is just about 5 times slower tha...
Is the LIKE operator case-sensitive with MSSQL Server?
...al_cp1_cs_as
(d) To create a column using a different collation
create table exampletable (
examplecolumn varchar(10) collate sql_latin1_general_cp1_ci_as null
)
(e) To modify a column collation
alter table exampletable
alter column examplecolumn varchar(10) collate sql_latin1_general_cp1...
Hibernate: “Field 'id' doesn't have a default value”
...any cases this problem can also be resolved by just dropping the offending table (or tables), assuming that Hibernate is set up to automatically create/manage the DB schema. To drop tables from a managed schema, SET foreign_key_checks = 0; is your friend. Just be sure to SET foreign_key_checks = 1...
SQL Server Management Studio alternatives to browse/edit tables and run queries [closed]
...
I strongly feel that we can't edit tables and can't run queries with hints using LINQ
– bjan
May 18 '12 at 5:28
1
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