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Notes on SQL commands

Basic SQL Queries (for SQL Server)

--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME

SQLite

Open a .db file in terminal

sqlite3 chat.db

View tables in database

.tables

View column names of a given table

PRAGMA table_info(table_name);

How to exit session

exit;

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Notes on SQL commands
Basic SQL Queries (for SQL Server)
--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME
SQLite
Open a .db file in terminal
sqlite3 chat.db
View tables in database
.tables
View column names of a given table
PRAGMA table_info(table_name);
How to exit session
exit;

, 'i');
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style.textContent = '
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Notes on SQL commands
Basic SQL Queries (for SQL Server)
--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME
SQLite
Open a .db file in terminal
sqlite3 chat.db
View tables in database
.tables
View column names of a given table
PRAGMA table_info(table_name);
How to exit session
exit;

, 'i');
if (__m === '*' || __re.test(location.href)) {
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ProgrammingNotes/sql.md at master · palpen/ProgrammingNotes · GitHub
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Notes on SQL commands
Basic SQL Queries (for SQL Server)
--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME
SQLite
Open a .db file in terminal
sqlite3 chat.db
View tables in database
.tables
View column names of a given table
PRAGMA table_info(table_name);
How to exit session
exit;

, 'i');
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'fbclid', 'gclid', 'dclid', 'msclkid', 'yclid',
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var __m = "youtube.com";
var __re = new RegExp('^' + "youtube\\.com" + '
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Notes on SQL commands
Basic SQL Queries (for SQL Server)
--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME
SQLite
Open a .db file in terminal
sqlite3 chat.db
View tables in database
.tables
View column names of a given table
PRAGMA table_info(table_name);
How to exit session
exit;

, 'i');
if (__m === '*' || __re.test(location.href)) {
// Auto-enable theater mode on YouTube
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function tryTheater() {
var btn = document.querySelector('button[aria-label="Theater mode"], ytd-player #player button[title="Theater mode"]');
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lastUrl = location.href;
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observer.observe(document.body, { childList: true, subtree: true });
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})();
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try {
var __m = "*";
var __re = new RegExp('^' + ".*" + '
ProgrammingNotes/sql.md at master · palpen/ProgrammingNotes · GitHub
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Notes on SQL commands
Basic SQL Queries (for SQL Server)
--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME
SQLite
Open a .db file in terminal
sqlite3 chat.db
View tables in database
.tables
View column names of a given table
PRAGMA table_info(table_name);
How to exit session
exit;

, 'i');
if (__m === '*' || __re.test(location.href)) {
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})();
})();
ProgrammingNotes/sql.md at master · palpen/ProgrammingNotes · GitHub
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Notes on SQL commands
Basic SQL Queries (for SQL Server)
--- Get all unique values of columnSELECT DISTINCT column
FROM table
--- Get unique values of column and the count for eachSELECT column, COUNT(column)
FROM table
GROUP BY column
-- Get count of distinct values in columnSELECTCOUNT(DISTINCT column)
FROM table
-- Count number of rows that satisfy conditions (e.g. column>0, column=10)SELECTCOUNT(*)
FROM table
WHERE condition1
AND condition2
-- List all columns for the table in DBNAME..TABLENAME
USE DBNAME
SELECT COLUMN_NAME FROMINFORMATION_SCHEMA.COLUMNSWHERE TABLE_NAME='TABLENAME'ORDER BY COLUMN_NAME
SQLite
Open a .db file in terminal
sqlite3 chat.db
View tables in database
.tables
View column names of a given table
PRAGMA table_info(table_name);
How to exit session
exit;