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What are the performance characteristics of sqlite with very large database files? [closed]
...application).
The tests involve a single sqlite file with either a single table, or multiple tables. Each table had about 8 columns, almost all integers, and 4 indices.
The idea was to insert enough data until sqlite files were about 50GB.
Single Table
I tried to insert multiple rows into a sqli...
SQL Server SELECT INTO @variable?
...
You cannot SELECT .. INTO .. a TABLE VARIABLE. The best you can do is create it first, then insert into it. Your 2nd snippet has to be
DECLARE @TempCustomer TABLE
(
CustomerId uniqueidentifier,
FirstName nvarchar(100),
LastName nvarchar(100),
...
mysql update column with value from another table
I have two tables, both looking like
8 Answers
8
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How do I change db schema to dbo
I imported a bunch of tables from an old sql server (2000) to my 2008 database. All the imported tables are prefixed with my username, for example: jonathan.MovieData . In the table properties it lists jonathan as the db schema. When I write stored procedures I now have to include jonathan....
How do you change the datatype of a column in SQL Server?
... varchar(50) to a nvarchar(200) . What is the SQL command to alter this table?
8 Answers
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Equal sized table cells to fill the entire width of the containing table
...th relative sizing) to make a row of cells stretch the entire width of the table within which it is contained?
3 Answers
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Inner join vs Where
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No! The same execution plan, look at these two tables:
CREATE TABLE table1 (
id INT,
name VARCHAR(20)
);
CREATE TABLE table2 (
id INT,
name VARCHAR(20)
);
The execution plan for the query using the inner join:
-- with inner join
EXPLAIN PLAN FOR
SELECT * FRO...
When to use a View instead of a Table?
When should a View actually be used over an actual Table? What gains should I expect this to produce?
8 Answers
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How to copy from CSV file to PostgreSQL table with headers in CSV file?
I want to copy a CSV file to a Postgres table. There are about 100 columns in this table, so I do not want to rewrite them if I don't have to.
...
How to write DataFrame to postgres table?
...te_engine('postgresql://scott:tiger@localhost:5432/mydatabase')
df.to_sql('table_name', engine)
You are correct that in pandas up to version 0.13.1 postgresql was not supported. If you need to use an older version of pandas, here is a patched version of pandas.io.sql: https://gist.github.com/jor...