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List all tables in postgresql information_schema
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You should be able to just run select * from information_schema.tables to get a listing of every table being managed by Postgres for a particular database.
You can also add a where table_schema = 'information_schema' to see just the tables in the informat...
How do I select the “last child” with a specific class name in CSS? [duplicate]
How do I select the "last child" with the class name: list ?
6 Answers
6
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Get contentEditable caret index position
...tion(editableDiv) {
var caretPos = 0,
sel, range;
if (window.getSelection) {
sel = window.getSelection();
if (sel.rangeCount) {
range = sel.getRangeAt(0);
if (range.commonAncestorContainer.parentNode == editableDiv) {
caretPos = range.endOffset;
}
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SQL to find the number of distinct values in a column
I can select all the distinct values in a column in the following ways:
11 Answers
11
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SQL statement to get column type
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Using SQL Server:
SELECT DATA_TYPE
FROM INFORMATION_SCHEMA.COLUMNS
WHERE
TABLE_NAME = 'yourTableName' AND
COLUMN_NAME = 'yourColumnName'
share
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How to get a list of user accounts using the command line in MySQL?
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Use this query:
SELECT User FROM mysql.user;
Which will output a table like this:
+-------+
| User |
+-------+
| root |
+-------+
| user2 |
+-------+
As Matthew Scharley points out in the comments on this answer, you can group by the ...
Display names of all constraints for a table in Oracle SQL
...CONS_COLUMNS view to see the table columns and corresponding constraints:
SELECT *
FROM user_cons_columns
WHERE table_name = '<your table name>';
FYI, unless you specifically created your table with a lower case name (using double quotes) then the table name will be defaulted to upper ca...
Spring Boot JPA - configuring auto reconnect
...1.3
spring.datasource.testOnBorrow=true
spring.datasource.validationQuery=SELECT 1
As djxak noted in the comment, 1.4+ defines specific namespaces for the four connections pools Spring Boot supports: tomcat, hikari, dbcp, dbcp2 (dbcp is deprecated as of 1.5). You need to check which connection po...
OnChange event handler for radio button (INPUT type=“radio”) doesn't work as one value
...ame attribute myRadios to read the variable prev which holds the currently selected radio. A comparison is done within each click handler to decide if the clicked radio is the same as the one stored in prev and if not then the currently clicked radio is stored there. Within the click handler, you ha...
Simulate CREATE DATABASE IF NOT EXISTS for PostgreSQL?
...k around it from within psql by executing the DDL statement conditionally:
SELECT 'CREATE DATABASE mydb'
WHERE NOT EXISTS (SELECT FROM pg_database WHERE datname = 'mydb')\gexec
The manual:
\gexec
Sends the current query buffer to the server, then treats each column of each row of the query's outpu...