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How to concatenate columns in a Postgres SELECT?
... an explicit coercion to text [...]
Bold emphasis mine. The 2nd example (select a||', '||b from foo) works for any data types since the untyped string literal ', ' defaults to type text making the whole expression valid in any case.
For non-string data types, you can "fix" the 1st statement by c...
How do I list all the columns in a table?
...
For Oracle (PL/SQL)
SELECT column_name
FROM user_tab_cols
WHERE table_name = 'myTableName'
For MySQL
SHOW COLUMNS FROM table_name
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MySQL Conditional Insert
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If your DBMS does not impose limitations on which table you select from when you execute an insert, try:
INSERT INTO x_table(instance, user, item)
SELECT 919191, 123, 456
FROM dual
WHERE NOT EXISTS (SELECT * FROM x_table
WHERE user = ...
Best practices for SQL varchar column length [closed]
...hen you need to worry about it and make them smaller. But if you only ever select 1 row from that table, then you can just make them all 255 and it won't matter.
See: What are the optimum varchar sizes for MySQL?
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SQL: capitalize first letter only [duplicate]
...t only for displaying and do not need the actual data in table to change:
SELECT UPPER(LEFT(word,1))+LOWER(SUBSTRING(word,2,LEN(word))) FROM [yourtable]
Hope this helps.
EDIT: I realised about the '-' so here is my attempt to solve this problem in a function.
CREATE FUNCTION [dbo].[CapitalizeFi...
string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)
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The best practice is selecting the most appropriate one.
.Net Framework 4.0 Beta 2 has a new IsNullOrWhiteSpace() method for
strings which generalizes the IsNullOrEmpty() method to also include other white
space besides empty string.
...
How can I unit test Arduino code?
...tiplex four 7 segment displays, one port driving the segments and a second selecting the display. The display code interfaces with the displays via SetSegmentData(char) and SetDisplay(char). I can mock these in my C++ test rig and check that I get the data I expect. For the target I use #define so t...
How do I find a stored procedure containing ?
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SELECT ROUTINE_NAME, ROUTINE_DEFINITION
FROM INFORMATION_SCHEMA.ROUTINES
WHERE ROUTINE_DEFINITION LIKE '%Foo%'
AND ROUTINE_TYPE='PROCEDURE'
SELECT OBJECT_NAME(id)
FROM SYSCOMMENTS
WHERE [text] LIKE...
Is there any connection string parser in C#?
...here(kvp => kvp.Contains('='))
.Select(kvp => kvp.Split(new char[] { '=' }, 2))
.ToDictionary(kvp => kvp[0].Trim(),
kvp => kvp[1].Trim(),
...
What is the direction of stack growth in most modern systems?
... else's code.
The processors and their direction are:
x86: down.
SPARC: selectable. The standard ABI uses down.
PPC: down, I think.
System z: in a linked list, I kid you not (but still down, at least for zLinux).
ARM: selectable, but Thumb2 has compact encodings only for down (LDMIA = increment ...