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SELECT INTO a table variable in T-SQL
Got a complex SELECT query, from which I would like to insert all rows into a table variable, but T-SQL doesn't allow it.
8...
Remove Primary Key in MySQL
... an index such that it is possible to perform the equivalent of an indexed SELECT MAX(ai_col) lookup on the table to obtain the maximum column value. Typically, this is achieved by making the column the first column of some table index.
– Quassnoi
Sep 23 '13 at...
How to delete from multiple tables in MySQL?
...nd filter on indices? 15k x 15k x 15k x 15k 15k x 15k is 11 million. Did a SELECT take similarly long?
– Paul Draper
May 22 '14 at 20:07
6
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Cleanest way to build an SQL string in Java
...uild an SQL string to do database manipulation (updates, deletes, inserts, selects, that sort of thing) - instead of the awful string concat method using millions of "+"'s and quotes which is unreadable at best - there must be a better way.
...
How to annotate MYSQL autoincrement field with JPA annotations
...oblem is saving the object Operator into MySQL DB.
Prior to save, I try to select from this table and it works, so is connection to db.
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How do you find the disk size of a Postgres / PostgreSQL table and its indexes
...
Try the Database Object Size Functions. An example:
SELECT pg_size_pretty(pg_total_relation_size('"<schema>"."<table>"'));
For all tables, something along the lines of:
SELECT
table_schema || '.' || table_name AS table_full_name,
pg_size_pretty(pg_total_...
PHP & mySQL: Year 2038 Bug: What is it? How to solve it?
...ything, I asked my backend (MSSQL) to do this job instead of PHP!
$qry = "select DATEADD(month, 1, :date) next_date ";
$rs_tmp = $pdo->prepare($qry);
$rs_tmp->bindValue(":date", '2038/01/15');
$rs_tmp->execute();
$row_tmp = $rs_tmp->fetch(PDO::FETCH_ASSOC);
echo $row_tmp['next_date'];
...
Create an index on a huge MySQL production table without table locking
...s).
Test Script:
(
for n in {1..50}; do
#(time mysql -uroot -e 'select * from website_development.users where id = 41225\G'>/dev/null) 2>&1 | grep real;
(time mysql -uroot -e 'update website_development.users set bio="" where id = 41225\G'>/dev/null) 2>&1 | grep r...
Selecting data from two different servers in SQL Server
How can I select data in the same query from two different databases that are on two different servers in SQL Server?
15 An...
mysql实现split分割字符串（length, SUBSTRING_INDEX, substring） - 数据...
...串，从pos起直到结束
以下通过一个例子查看效果：
SELECT SUBSTRING_INDEX(contentid, '-', 1) first, substring(contentid, 2+length(SUBSTRING_INDEX(contentid, '-', 1))) second, contentid FROM `table_xxx`
mysql split 分割字符串