varchar_开发者

Postgresql - change the size of a varchar column to lower length

I have a question about the ALT开发者_运维问答ER TABLE command on a really large table (almost 30 millions rows).[详细]

2023-04-12 19:37 分类：问答

Converting date/time in sql to string

Is there any way that I can convert the DateTime SQL value of this: 2011-10-11 00:00:00.000 to a string formatted exactly the same?开发者_运维知识库[详细]

2023-04-12 05:07 分类：问答

Varchar type and performance issues

I\'m modelling a database and I want to ask about the Varchar type. Is there any performance difference between Varchar(50) and Varchar(100)?[详细]

2023-04-11 20:22 分类：问答

When increasing the size of VARCHAR column on a large table could there be any problems?

I\'m using SQL Server 2008 and I need to make a VARCHAR field bigger, from (200 to 1200) on a table with about 500k rows.What I need to know is if there are any issues I have not considered.[详细]

2023-04-07 04:57 分类：问答

Symfony Error on Form Submission .... "must be an instance of varchar, string given,"

Running Symfony2 Upon submitting a form, here is the error I get: Catchable Fatal Error: Argument 1 passed to Depot\\StarterBundle\\Entity\\Application::setPropAddr() must be an ins开发者_开发知识库[详细]

2023-04-06 18:19 分类：问答

how to update a VARCHAR column value with RegEx?

I need to update the values from a VARCHAR column in a MySQL database from YYMMDDSXXXXX to YYMMDDSXXXX, where YY is year (i.e. 11 for 2011), MM is month (i.e. 09 for September), DD is day (i.e. 15), S[详细]

2023-04-05 17:38 分类：问答

In mysql, does the size of VARCHAR(size) make any difference in performance? [duplicate]

This question already has answers here: Closed 11开发者_StackOverflow中文版 years ago. Possible Duplicate:[详细]

2023-04-04 07:18 分类：问答

Why specify a length for character varying types

Referring to the Postgres Documentation on Character Types, I am unclear on the point of specifying a length for character varying (varchar) types.[详细]

2023-04-03 03:28 分类：问答

How can I change the format of the dates produced when using ALTER COLUMN to convert a datetime column to varchar?

I have a datetime column that I need to alter to be a varchar column. Using the statement below, the strings produced have this format: \"Jan 18 20105:28PM\"[详细]

2023-04-01 07:19 分类：问答