Datatypes

Date Type: Each value manipulated by Oracle Database has a data type. The data type of a value associates a fixed set of properties with the value. Data type is associated with a specific storage format, constraints, and a valid range of values

There are Two Types:  1. Scalar Datatypes

                                     2. Composite Datatypes


Scalar Datatypes:

PL/SQL Scalar Data Types and Subtypes

Date Type	Description
Numeric	Numeric values on which arithmetic operations are performed.
Character	Alphanumeric values that represent single characters or strings of characters.
Boolean	Logical values on which logical operations are performed.
Datetime	Dates and times.

PL/SQL Numeric Data Types and Subtypes

Data Type	Description
PLS_INTEGER	Signed integer in range -2,147,483,648 through 2,147,483,647, represented in 32 bits
BINARY_INTEGER	Signed integer in range -2,147,483,648 through 2,147,483,647, represented in 32 bits
BINARY_FLOAT	Single-precision IEEE 754-format floating-point number
BINARY_DOUBLE	Double-precision IEEE 754-format floating-point number
NUMBER(prec, scale)	Fixed-point or floating-point number with absolute value in range 1E-130 to (but not including) 1.0E126. A NUMBER variable can also represent 0.
DEC(prec, scale)	ANSI specific fixed-point type with maximum precision of 38 decimal digits.
DECIMAL(prec, scale)	IBM specific fixed-point type with maximum precision of 38 decimal digits.
NUMERIC(pre, secale)	Floating type with maximum precision of 38 decimal digits.
DOUBLE PRECISION	ANSI specific floating-point type with maximum precision of 126 binary digits (approximately 38 decimal digits)
FLOAT	ANSI and IBM specific floating-point type with maximum precision of 126 binary digits (approximately 38 decimal digits)
INT	ANSI specific integer type with maximum precision of 38 decimal digits
INTEGER	ANSI and IBM specific integer type with maximum precision of 38 decimal digits
SMALLINT	ANSI and IBM specific integer type with maximum precision of 38 decimal digits
REAL	Floating-point type with maximum precision of 63 binary digits (approximately 18 decimal digits)

PL/SQL Character Data Types and Subtypes

Data Type	Description
CHAR	Fixed-length character string with maximum size of 32,767 bytes
VARCHAR2	Variable-length character string with maximum size of 32,767 bytes
RAW	Variable-length binary or byte string with maximum size of 32,767 bytes, not interpreted by PL/SQL
NCHAR	Fixed-length national character string with maximum size of 32,767 bytes
NVARCHAR2	Variable-length national character string with maximum size of 32,767 bytes
LONG	Variable-length character string with maximum size of 32,760 bytes
LONG RAW	Variable-length binary or byte string with maximum size of 32,760 bytes, not interpreted by PL/SQL
ROWID	Physical row identifier, the address of a row in an ordinary table
UROWID	Universal row identifier (physical, logical, or foreign row identifier)

PL/SQL Datetime and Interval Types

Field Name	Valid Datetime Values	Valid Interval Values
YEAR	-4712 to 9999 (excluding year 0)	Any nonzero integer
MONTH	01 to 12	0 to 11
DAY	01 to 31 (limited by the values of MONTH and YEAR, according to the rules of the calendar for the locale)	Any nonzero integer
HOUR	00 to 23	0 to 23
MINUTE	00 to 59	0 to 59
SECOND	00 to 59.9(n), where 9(n) is the precision of time fractional seconds	0 to 59.9(n), where 9(n) is the precision of interval fractional seconds
TIMEZONE_HOUR	-12 to 14 (range accommodates daylight savings time changes)	Not applicable
TIMEZONE_MINUTE	00 to 59	Not applicable
TIMEZONE_REGION	Found in the dynamic performance view V$TIMEZONE_NAMES	Not applicable
TIMEZONE_ABBR	Found in the dynamic performance view V$TIMEZONE_NAMES	Not

PL/SQL Large Object (LOB) Data Types

Data Type	Description	Size
BFILE	Used to store large binary objects in operating system files outside the database.	System-dependent. Cannot exceed 4 gigabytes (GB).
BLOB	Used to store large binary objects in the database.	8 to 128 terabytes (TB)
CLOB	Used to store large blocks of character data in the database.	8 to 128 TB
NCLOB	Used to store large blocks of NCHAR data in the database.	8 to 128 TB

Composite Datatypes:

             There are two types 1. Records

                                              2. Collections

                                                        i. Index-by tables or Associative array

                                                                             ii. Nested table

                                                                             iii. Variable-size array or Varray 

SQL Functions

• Select
• Simple select statement
• Column
• ROWID / ROWNUM
• Arithmetic
• Distinct
• NULL
• Where
• DUAL Table
• SQL Comparison Operators
• ALL,ANY
• AND, OR, and NOT
• BETWEEN ... AND matches a range of values
• IN matches lists of values
• LIKE(NOT LIKE) matches patterns in strings
• IS NULL(IS NOT NULL) matches null values
• Group

o    ROLLUP,

o    CUBE,

o    GROUP BY,

o    GROUPING,

o    GROUPING SETS

• Having
• Order
• Joins
• Equijoin
• Non-EquiJoin
• Outer Join,
• Self Join
• Cartesian Products

• Set Operators
• UNION ALL, UNION, INTERSECT, MINUS
• CASE
• Hierarchical Queries
• Pseudo columns
• External Table

DATA TYPES

• CHAR(n)
• VARCHAR2(n)
• Numeric
• Date
• Timestamp
• Time intervals
• CLOB
• BLOB
• BFILE
• Simple_Integer

SUB QUERIES

• Single-row subqueries
• Single-row subquery Errors
• Multiple-Row Subqueries
• Multiple-column subqueries
• Correlated subqueries
• Nested subqueries

TABLE

• Describe
• Insert
• Update, 
• Returning
• Delete
• Alter
• Merge
• Primary Key
• Foreign Key
• Default Values
• Transactions
• Table Creation, 
• Rename, 
• Truncating, 
• Data Dictionary, 
• Dropping
• Columns
• Constraints
• Comments
• Sequence
• Index
• Views
• Flashback Data Archives
• Commit
• Rollback
• Savepoint

USER, PRIVILEGE, ROLE

• User
• System Privileges
• Object Privileges
• Synonyms
• Roles
• Auditing

DATA DICTIONARIES

• ALL views have information about all accessible data.
• USER views have information about your own data.
• DBA views have database-wide information.
• V$ views are dynamic performance views.

Oracle function list in alphabetical order

Name	Description
ABS(x)	absolute value of x
ACOS(n)	Arccosine
ADD_MONTHS(d, n)	Date d plus n months
ASCII	Gives the ASCII value of the first character of a string.
ASCIISTR	Converts x to an ASCII string, where x may be a string in any character set.
ASIN(n)	Arcsine of n
ATAN(n)	Arctangent of n
ATAN2(x,y)	Returns the arctangent of x and y.
AVG	Calculates the average
BIN_TO_NUM	Converts a binary number x to a NUMBER.
BITAND(x,y)	a bitwise AND on x and y.
CAST(x AS type)	Converts x to a compatible type specified in type.
CEIL	Returns the ceiling value (next highest integer above a number).
CHARTOROWID(x)	Converts x to a ROWID.
CHR(n)	Character with ASCII value n
COALESCE(a, b, ...)	The first not NULL argument (and NULL if all arguments are NULL)
COMPOSE(x)	Converts x to a Unicode string in normalized form.
CONCAT	Concatenates two strings
CONVERT(x,source_char_set,dest_char_set)	Converts x from source_char_set to dest_char_set.
COS(n)	Cosine of n (n expressed in radians)
COSH(n)	Hyperbolic cosine of n
COUNT(x)	Returns the number of rows returned by a query involving x
CUBE	Returns rows containing a subtotal for all combinations of columns
CUME_DIST()	Returns the position of a value relative to a group.
CURRENT_DATE	returns the current date in the local time zone in the database session
CURRENT_TIMESTAMP	Returns a TIMESTAMP WITH TIME ZONE for the session
DBTIMEZONE	Returns the time zone for the database
DECODE	Use it as if then else statement
DECOMPOSE(x)	Decomposes the string into the same character set as x and convert x to a Unicode string.
DENSE_RANK	Rank the rows and does not skip ties
EXP	Returns e raised to a value.
EXTRACT	Extracts and returns the year, month, day, hour, minute, second, or time zone from x.
EXTRACT(c FROM d)	Extract date/time component c from expression d
FIRSTFirst	gets the first values in an ordered group.
First_value	Gets the first rows in a window.
FLOOR	Returns the floor value (next lowest integer below number).
FROM_TZ(x, time_zone)	Merges xand time_zone into one value.
GREATEST(a, b, ...)	Greatest value of the function arguments
GROUP_ID	Removes duplicate rows returned by a ROLLUP or CUBE.
GROUPING	Deals with NULL value for ROLLUP and CUBE
GROUPING_ID	Returns the decimal equivalent of the GROUPING bit vector.
HEXTORAW(x)	Converts the character x containing hexadecimal digits (base-16) to a binary number (RAW).
Hypothetical	Rank and Distribution Functions
INITCAP	Changes the first letter of a string or series of words into uppercase.
INSTR	Returns the beginning location of a pattern in a given string.
LAG
LAST	gets the last values in an ordered group.
LAST_DAY(d)	Last day of the month containing date d
Last_value	Gets the last rows in a window.
LEAST(a, b, ...)	Least value of the function arguments
LENGTH	Returns the length of a string.
LN(n),LOG(m,n)	Natural logarithm, and logarithm base m
LOCALTIMESTAMP	Returns a TIMESTAMP for the session.
LOWER	Converts every letter of a string to lowercase.
LPAD	Adds a specified set of characters to the left of the original string.
LTRIM	Removes a set of characters from the left of a string.
MAX	Returns the maximum value
MEDIAN	Returns the median value
MIN	Returns the minimum value
Mod	Returns The Remainder Of N/M Where Both N And M Are Integers.
MONTHS_BETWEEN(d, e)	Months between dates d and e
NEW_TIME(x,time_zone1,time_zone2)	Converts x from time_zone1 to time_zone2
NEW_TIME(d, z1, z2)	Convert date/time d from time zone z1 to z2
NEXT_DAY(d, weekday)	The first weekday (mon, tue, etc.) after d
NTILE	Groups data by putting data into a number of percentile groups
NULLIF(a, b)	NULL if a = b; otherwise a
NUMTODSINTERVAL(x)	Converts the number x to an INTERVAL DAY TO SECOND.
NumToDSInterval	Converts number x to INTERVAL DAY TO SECOND.
NUMTOYMINTERVAL(x)	Converts the number x to an INTERVAL YEAR TO MONTH.
NumToYMInterval	Converts number x to INTERVAL YEAR TO MONTH.
NVL	Returns value if x is null; otherwise x is returned.
NVL2	Returns value1 if x is not null; otherwise value2 is returned.
PARTITION BY	Separate data groups and perform calculation within that group
PERCENT_RANK()	Returns the percent rank of a value relative to a group.
PERCENTILE_CONT	Checks the percent rank values in each group
PERCENTILE_DISC	Checks the cumulative distribution values
POWER	Returns value raised to some exponential power.
RANK	Returns the rank of items in a group and leaves a gap for a tie.
RATIO_TO_REPORT()	Ratio to report
RAWTOHEX(x)	Converts the binary number (RAW) x to a VARCHAR2string in equivalent hexadecimal number.
RAWTONHEX(x)	Converts the binary number (RAW) x to an NVARCHAR2string in the equivalent hexadecimal number.
REGEXP_COUNT	Returns the number of times the pattern is found.
REGEXP_INSTR	Returns the location of a pattern in a given string and supports the regular expression.
REGEXP_LIKE	Searches x for the regular expression defined in the pattern parameter.
REGEXP_REPLACE	Replaces string with the regular expression matching supports
REGEXP_SUBSTR	Returns the substring with the regular expression matching supports
REGR_AVGX(y, x)	Returns the average of x after eliminating x and y pairs
REGR_AVGY(y, x)	Returns the average of y after eliminating x and y pairs
REGR_COUNT(y, x)	Returns the number of non-null number pairs that are used to fit the regression line
REGR_INTERCEPT(y, x)	Returns the intercept on the y-axis of the regression line
REGR_R2(y, x)	Returns the coefficient of determination of the regression line
REGR_SLOPE(y, x)	Returns the slope of the regression line
REGR_SXX(y, x)	Returns REG_COUNT (y, x) * VAR_POP(x)
REGR_SXY(y, x)	Returns REG_COUNT (y, x) * COVAR_POP(y, x)
REGR_SYY(y, x)	Returns REG_COUNT (y, x) * VAR_POP (y)
REMAINDER(n1, n2)	Identifies the multiple of n2 that is nearest to n1, and returns the difference between those two values.
REPLACE	Does the string replacement
ROLLUP	Returns a row containing a subtotal
ROUND(d[, fmt])	d rounded on fmt (the default for fmt is midnight)
ROUND	Returns the number rounded to nearest value, adjusts precision.
ROW_NUMBER	row number for ranking
ROWIDTOCHAR(x)	Converts the ROWID x to a VARCHAR2 string.
ROWIDTONCHAR(x)	Converts the ROWID x to an NVARCHAR2 string.
ROWNUM	pseudo-column and is calculated as rows are retrieved
RPAD	Adds a specified set of characters to the right of the original string.
RTRIM	Removes a set of characters from the right of a string.
SESSIONTIMEZONE	Returns the database session time zone
Sign	Returns 1 If The Argument Is Positive; -1 If The Argument Is Negative; And 0 If The Argument Is Negative.
SIN(n)	Sine of n (n expressed in radians)
SINH(n)	Hyperbolic sine of n
SOUNDEX	Converts a string to a code value based on similar sounds.
Sqrt(x)	Square Root Of x
STDDEV	Returns the standard deviation
String||String	Concatenates two strings.
SUBSTR	Retrieves a portion.
SUM	Returns the sum
SYS_EXTRACT_UTC(x)	Converts the TIMESTAMP WITH TIMEZONE x to a TIMESTAMP in UTC.
SYS_EXTRACT_UTC	Extracts the UTC from a datetime value.
Sysdate	Returns the current operating system date from database server
SYSTIMESTAMP	Returns a TIMESTAMP WITH TIME ZONE for the database.
TAN(n)	Tangent of n (n expressed in radians)
TANH(n)	Hyperbolic tangent of n
TO_BINARY_DOUBLE(x)	Converts x to a BINARY_DOUBLE.
TO_BINARY_FLOAT(x)	Converts x to a BINARY_FLOAT.
TO_BLOB(x)	Converts x to a binary large object (BLOB).
TO_CHAR	Converts number and date value to string and format
TO_CLOB(x)	Converts x to a character large object (CLOB). A CLOBis used to store large amounts of character data.
TO_DATE	Converts string to date value
TO_DSINTERVAL(x)	Converts the string x to an INTERVAL DAY TO SECOND.
TO_DSInterval	Converts string x to INTERVAL DAY TO SECOND.
TO_MULTI_BYTE(x)	Converts the single-byte characters in x to the corresponding multi-byte characters.
TO_NCHAR(x)	Converts x in the database character set to an NVARCHAR2 string.
TO_NCLOB(x)	Converts x to a large object NCLOB.
TO_NUMBER(x [, format]	Converts x to a NUMBER.
TO_SINGLE_BYTE(x)	Converts the multi-byte characters in x to the corresponding single-byte characters.
TO_TIMESTAMP(x)	Converts the string x to a TIMESTAMP.
TO_TIMESTAMP(x, [format])	Converts the string x to a TIMESTAMP.
TO_TIMESTAMP_TZ(x)	Converts the string xto a TIMESTAMP WITH TIME ZONE.
TO_TIMESTAMP_TZ(x, [format])	Converts the string x to a TIMESTAMP WITH TIMEZONE.
TO_YMINTERVAL(x)	Converts the string x to an INTERVAL YEAR TO MONTH.
TO_YMInterval	Converts string x to INTERVAL YEAR TO MONTH.
TRANSLATE(x,from_string, to_string)	Converts all occurrences of from_string in x to to_string.
TRANSLATE	Replaces a string character by character.
TRIM	Removes a set of characters from both sides.
TRUNC(d[, fmt])	d truncated on fmt (the default for fmt is midnight)
TRUNC	Returns the truncated value (removes decimal part of a number, precision adjustable).
TZ_OFFSET(time_zone)	Returns the offset for time_zone in hours and minutes
UNISTR(x)	Converts the characters in x to an NCHAR character.
UPPER	Converts every letter to uppercase.
VARIANCE	Returns the variance
VSIZE	Returns the storage size.