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How many database indexes is too many?
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It depends on the operations that occur on the table.
If there's lots of SELECTs and very few changes, index all you like.... these will (potentially) speed the SELECT statements up.
If the table is heavily hit by UPDATEs, INSERTs + DELETEs ... these will be very slow with lots of indexes since t...
unsigned APK can not be installed
...ps.)
Install your app onto the emulator.
Once it is installed goto DDMS, select the current running app under the devices window. This will then show all the files related to it under the file explorer.
Under file explorer go to data->app and select your APK (which is the package name of the ap...
Get the new record primary key ID from MySQL insert query?
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Eg:
INSERT INTO table_name (col1, col2,...) VALUES ('val1', 'val2'...);
SELECT LAST_INSERT_ID();
This will get you back the PRIMARY KEY value of the last row that you inserted:
The ID that was generated is maintained in the server on a per-connection basis. This means that the value returne...
TextEnhancer拓展 - 增强App中的文本格式 - App Inventor 2 拓展 - 清泛IT社区，为创新赋能！
...gh.
blocks (32)[size=15.008px]822×162 16.7 KB
[size=15.008px]SetTextSelectable:Enable or disable text selection for the specified label. true to enable text selection, false to disable text selection.
blocks (30)[size=15.008px]784×162 16.1 KB
[size=15.008px]HighlightText:Highlight spec...
Google Play Services Library update and missing symbol @integer/google_play_services_version
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control click -> properties -> android -> libraries, add -> select the project you just imported -> ok
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Inserting multiple rows in mysql
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it's also possible to use INSERT INTO Table SELECT 1, '14/05/2012', 3 UNION SELECT 2, '05/14/2012', 3. of course, this will only be better of the inserted values are coming from different tables.
– Zohar Peled
Jun 1 '15 at 9:18
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PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...and sequences too. Here's what I did:
Tables:
for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do psql -c "alter table \"$tbl\" owner to NEW_OWNER" YOUR_DB ; done
Sequences:
for tbl in `psql -qAt -c "select sequence_name from information_schem...
How to execute a bash command stored as a string with quotes and asterisk [duplicate]
...quotes.
MYSQL='mysql AMORE -u username -ppassword -h localhost -e'
QUERY="SELECT "'*'" FROM amoreconfig" ;# <-- "double"'single'"double"
eval $MYSQL "'$QUERY'"
Bonus: It also reads nice: eval mysql query ;-)
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How to swap the buffers in 2 windows emacs
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If you just want to swap windows (independent on the selected one), you can use the following (defun win-swap () "Swap windows using buffer-move.el" (interactive) (if (null (windmove-find-other-window 'right)) (buf-move-left) (buf-move-right)))
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How to retrieve the current version of a MySQL database management system (DBMS)?
... and Windows.
When connected to a MySQL server with a client you can use
select version()
or
select @@version
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