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Sql

How to avoid error "aggregate functions are not allowed in WHERE"

sql
aggregate-functions
where-clause
having-clause

How long should SQL email fields be?

sql
database-design
email-validation
sql-best-practices

How do you run a single query through mysql from the command line?

sql
mysql
command-line
best-practices

How do I set a column value to NULL in SQL Server Management Studio?

sql
null-values
sql-server-management-studio
data-consistency

How do I see active SQL Server connections?

sql
database-administration
sql-server-performance
connection-management

How do I perform an IF...THEN in an SQL SELECT?

sql
conditional-statements
sql-syntax
best-practices

How do I pass a list as a parameter in a stored procedure?

sql
table-valued-parameters
string-split
sql-injection

How do I interpret precision and scale of a number in a database?

sql
decimal-precision
data-type-selection
sql-server-rounding

How do I flip a bit in SQL Server?

sql
bitwise-operations
sql-operations
data-type

How do I declare and assign a variable on a single line in SQL

sql
best-practices
data-type
variable-declaration

How do I check if a column is empty or null in MySQL?

sql
prompt-engineering
best-practices
performance

How does SELECT from two tables separated by a comma work? (SELECT * FROM T1, T2)

sql
join
performance
best-practices

How can I truncate a datetime in SQL Server?

sql
datetime-truncation
sql-server
date-functions

How can I select the first day of a month in SQL?

sql
date-manipulation
sql-functions
performance

How can I merge the columns from two tables into one output?

sql
join
union
left-outer-join

How can I get the number of records affected by a stored procedure?

sql
out-parameters
stored-procedures
row-count

How can I do SELECT UNIQUE with LINQ?

sql
linq
sql-queries
performance-optimization

How can I do 'insert if not exists' in MySQL?

sql
insert-ignore
sql-queries
database-management

How can I define a composite primary key in SQL?

sql
data-integrity
performance-optimization
database-design

How can I combine multiple rows into a comma-delimited list in Oracle?

sql
listagg
oracle
sql-functions
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