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How to delete or add column in SQLITE?
... as long as you do a create new table first instead of a create from select, it will have all those things.
– John Lord
Jul 3 '19 at 15:28
1
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Passing an array to a query using a WHERE clause
...y external input is sanitized.
$ids = join("','",$galleries);
$sql = "SELECT * FROM galleries WHERE id IN ('$ids')";
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Find rows with multiple duplicate fields with Active Record, Rails & Postgres
...
Tested & Working Version
User.select(:first,:email).group(:first,:email).having("count(*) > 1")
Also, this is a little unrelated but handy. If you want to see how times each combination was found, put .size at the end:
User.select(:first,:email).gro...
The SQL OVER() clause - when and why is it useful?
...ated values and then join it back to the original rowset, i.e. like this:
SELECT
orig.[Partition],
orig.Value,
orig.Value * 100.0 / agg.TotalValue AS ValuePercent
FROM OriginalRowset orig
INNER JOIN (
SELECT
[Partition],
SUM(Value) AS TotalValue
FROM OriginalRowset
G...
Find the number of columns in a table
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SELECT COUNT(*)
FROM INFORMATION_SCHEMA.COLUMNS
WHERE table_catalog = 'database_name' -- the database
AND table_name = 'table_name'
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Count the number of occurrences of a string in a VARCHAR field?
...
This should do the trick:
SELECT
title,
description,
ROUND (
(
LENGTH(description)
- LENGTH( REPLACE ( description, "value", "") )
) / LENGTH("value")
) AS count
FROM <tab...
Import / Export database with SQL Server Server Management Studio
... if you want to also export the data, on the "Set Scripting Options" step, select the "Advanced" button and change "Types of data to script" from "Schema Only" to "Data Only" or "Schema and Data".
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How to execute raw SQL in Flask-SQLAlchemy app
...xecute("<sql here>")
or:
from sqlalchemy import text
sql = text('select name from penguins')
result = db.engine.execute(sql)
names = [row[0] for row in result]
print names
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Dynamic SELECT TOP @var In SQL Server
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SELECT TOP (@count) * FROM SomeTable
This will only work with SQL 2005+
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How to change collation of database, table, column?
...he OP asked:
How to change collation of database, table, column?
The selected answer just states it on table level.
Changing it database wide:
ALTER DATABASE <database_name> CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
Changing it per table:
ALTER TABLE <table_name> CON...