The best and most efficient way is to catch the “table not found” exception: this avoids the overhead of checking if the table exists twice; and doesn’t suffer from the problem that if the DROP fails for some other reason (that might be important) the exception is still raised to the caller: BEGIN EXECUTE IMMEDIATE … Read more
you should put those two dates between single quotes like.. select Date, TotalAllowance from Calculation where EmployeeId = 1 and Date between ‘2011/02/25’ and ‘2011/02/27’ or can use select Date, TotalAllowance from Calculation where EmployeeId = 1 and Date >= ‘2011/02/25’ and Date <= ‘2011/02/27’ keep in mind that the first date is inclusive, but … Read more
Using SELECT SELECT @ModelID = m.modelid FROM MODELS m WHERE m.areaid = ‘South Coast’ Using SET SET @ModelID = (SELECT m.modelid FROM MODELS m WHERE m.areaid = ‘South Coast’) See this question for the difference between using SELECT and SET in TSQL. Warning If this SELECT statement returns multiple values (bad to begin with): When … Read more
Lowest common denominator max URL length among popular web browsers: 2,083 (Internet Explorer) http://dev.mysql.com/doc/refman/5.0/en/char.html Values in VARCHAR columns are variable-length strings. The length can be specified as a value from 0 to 255 before MySQL 5.0.3, and 0 to 65,535 in 5.0.3 and later versions. The effective maximum length of a VARCHAR in MySQL 5.0.3 … Read more
What you are looking for are Linked Servers. You can get to them in SSMS from the following location in the tree of the Object Explorer: Server Objects–>Linked Servers or you can use sp_addlinkedserver. You only have to set up one. Once you have that, you can call a table on the other server like … Read more
use the float or real data types only if the precision provided by decimal (up to 38 digits) is insufficient Approximate numeric data types(see table 3.3) do not store the exact values specified for many numbers; they store an extremely close approximation of the value. (Technet) Avoid using float or real columns in WHERE clause … Read more
For MySQL 8+: use the recursive with syntax. For MySQL 5.x: use inline variables, path IDs, or self-joins. MySQL 8+ with recursive cte (id, name, parent_id) as ( select id, name, parent_id from products where parent_id = 19 union all select p.id, p.name, p.parent_id from products p inner join cte on p.parent_id = cte.id ) … Read more
from django.db.models import Q User.objects.filter(Q(income__gte=5000) | Q(income__isnull=True)) via Documentation
Using SQL Server: SELECT DATA_TYPE FROM INFORMATION_SCHEMA.COLUMNS WHERE TABLE_SCHEMA = ‘yourSchemaName’ AND TABLE_NAME = ‘yourTableName’ AND COLUMN_NAME = ‘yourColumnName’
UPDATE urls SET url = REPLACE(url, ‘domain1.example/images/’, ‘domain2.example/otherfolder/’)