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SQL—An Introduction Introduction to PROC SQL
SAS SQL #1SAS Structured Query Language, An Introduction
JC Wang
wang (WMU) SAS SQL #1 Lecture 19 1 / 20
SQL—An Introduction Introduction to PROC SQL
Outline
1 SQL—An IntroductionWhat is SQL
2 Introduction to PROC SQLSAS SQLQuery a TableSorting Query Output
wang (WMU) SAS SQL #1 Lecture 19 2 / 20
SQL—An Introduction Introduction to PROC SQL
What is SQL Language
Structured Query Language (SQL), a standardized, widely usedlanguage that retrieves / updates data in relational databases.Relation = concept similar to concept of a set in mathematicsRelations are represented physically as two-dimensional tables(arranged in rows and columns).
wang (WMU) SAS SQL #1 Lecture 19 3 / 20
SQL—An Introduction Introduction to PROC SQL
Outline
1 SQL—An IntroductionWhat is SQL
2 Introduction to PROC SQLSAS SQLQuery a TableSorting Query Output
wang (WMU) SAS SQL #1 Lecture 19 4 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
What PROC SQL Does
PROC SQL = SAS implementation of Structured Query Language. Itcan
generate reportsgenerate summary statisticsretrieve data from tables or viewscombine data from tables or viewscreate tables, views, and indexesupdate data values in PROC SQL tablesupdate / retrieve data from database management system(DBMS) tablesmodify PROC SQL table by adding, modifying, or droppingcolumns.
wang (WMU) SAS SQL #1 Lecture 19 5 / 20
SQL—An Introduction Introduction to PROC SQL
Comparison of Terminology
SQL tables = SAS data file = a filerows = observations = recordscolumns = variables = fieldsDBMS tables = tables from other vendors which can be accessedthrough SAS/ACCESSQueries retrieve data from a table, view, or DBMS with resultsconsisting of rows and columns from a table.SQL view contains a stored query (instruction only), i.e., a virtualtableSAS PROC SQL null values = missing values.
wang (WMU) SAS SQL #1 Lecture 19 6 / 20
SQL—An Introduction Introduction to PROC SQL
Comparison of Terminology
SQL tables = SAS data file = a filerows = observations = recordscolumns = variables = fieldsDBMS tables = tables from other vendors which can be accessedthrough SAS/ACCESSQueries retrieve data from a table, view, or DBMS with resultsconsisting of rows and columns from a table.SQL view contains a stored query (instruction only), i.e., a virtualtableSAS PROC SQL null values = missing values.
wang (WMU) SAS SQL #1 Lecture 19 6 / 20
SQL—An Introduction Introduction to PROC SQL
Comparison of Terminology
SQL tables = SAS data file = a filerows = observations = recordscolumns = variables = fieldsDBMS tables = tables from other vendors which can be accessedthrough SAS/ACCESSQueries retrieve data from a table, view, or DBMS with resultsconsisting of rows and columns from a table.SQL view contains a stored query (instruction only), i.e., a virtualtableSAS PROC SQL null values = missing values.
wang (WMU) SAS SQL #1 Lecture 19 6 / 20
SQL—An Introduction Introduction to PROC SQL
Comparison of Terminology
SQL tables = SAS data file = a filerows = observations = recordscolumns = variables = fieldsDBMS tables = tables from other vendors which can be accessedthrough SAS/ACCESSQueries retrieve data from a table, view, or DBMS with resultsconsisting of rows and columns from a table.SQL view contains a stored query (instruction only), i.e., a virtualtableSAS PROC SQL null values = missing values.
wang (WMU) SAS SQL #1 Lecture 19 6 / 20
SQL—An Introduction Introduction to PROC SQL
Syntax of PROC SQLbasic use
PROC SQL <options>;query-1;query-2;...more queries...QUIT;
a query = a run block. Upon submission, SAS executes the query.End PROC SQL with a QUIT since it’s interactive.
wang (WMU) SAS SQL #1 Lecture 19 7 / 20
SQL—An Introduction Introduction to PROC SQL
Syntax of PROC SQLbasic use
PROC SQL <options>;query-1;query-2;...more queries...QUIT;
a query = a run block. Upon submission, SAS executes the query.End PROC SQL with a QUIT since it’s interactive.
wang (WMU) SAS SQL #1 Lecture 19 7 / 20
SQL—An Introduction Introduction to PROC SQL
Syntax of a Queryfrom single table
SELECT input-columnsFROM tableWHERE cond-to-subset-input-rowsGROUP BY columnHAVING cond-to-subset-groupsORDER BY columns;
It’s a single statement in this order of clauses.SELECT and FROM are required.
wang (WMU) SAS SQL #1 Lecture 19 8 / 20
SQL—An Introduction Introduction to PROC SQL
Syntax of a Queryfrom single table
SELECT input-columnsFROM tableWHERE cond-to-subset-input-rowsGROUP BY columnHAVING cond-to-subset-groupsORDER BY columns;
It’s a single statement in this order of clauses.SELECT and FROM are required.
wang (WMU) SAS SQL #1 Lecture 19 8 / 20
SQL—An Introduction Introduction to PROC SQL
SELECT and FROM Clauses
SELECT input-columnsFROM table;
input-columns: a comma-separated ordered list of columns orthe wild-card ∗ (= all columns in table)table: one-word table (SAS data set) name or two-word namelibref.sas-data-set-name (usually the latter)use SELECT DISTINCT a-table-column to query only uniquevalues of the table column
wang (WMU) SAS SQL #1 Lecture 19 9 / 20
SQL—An Introduction Introduction to PROC SQL
SELECT and FROM Clauses
SELECT input-columnsFROM table;
input-columns: a comma-separated ordered list of columns orthe wild-card ∗ (= all columns in table)table: one-word table (SAS data set) name or two-word namelibref.sas-data-set-name (usually the latter)use SELECT DISTINCT a-table-column to query only uniquevalues of the table column
wang (WMU) SAS SQL #1 Lecture 19 9 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Input Columns in SELECT Clause
an input column can bea table columna quoted text stringa calculated columna column created by a simple CASE expressiona column created by a CASE-Operand expressiona column created by COALESCE function of columns
wang (WMU) SAS SQL #1 Lecture 19 10 / 20
SQL—An Introduction Introduction to PROC SQL
Dress Up Input Columns with Attributes
input-column <attributes>where attributes are blank-separated column attributes of
FORMAT=
INFORMAT=
LABEL=’text-string’ (or simply ’text-string’)LENGTH=
Use of LABEL=’#’ suppresses the column header.See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 11 / 20
SQL—An Introduction Introduction to PROC SQL
Dress Up Input Columns with Attributes
input-column <attributes>where attributes are blank-separated column attributes of
FORMAT=
INFORMAT=
LABEL=’text-string’ (or simply ’text-string’)LENGTH=
Use of LABEL=’#’ suppresses the column header.See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 11 / 20
SQL—An Introduction Introduction to PROC SQL
Dress Up Input Columns with Attributes
input-column <attributes>where attributes are blank-separated column attributes of
FORMAT=
INFORMAT=
LABEL=’text-string’ (or simply ’text-string’)LENGTH=
Use of LABEL=’#’ suppresses the column header.See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 11 / 20
SQL—An Introduction Introduction to PROC SQL
Dress Up Input Columns with Attributes
input-column <attributes>where attributes are blank-separated column attributes of
FORMAT=
INFORMAT=
LABEL=’text-string’ (or simply ’text-string’)LENGTH=
Use of LABEL=’#’ suppresses the column header.See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 11 / 20
SQL—An Introduction Introduction to PROC SQL
Using Column Alias
input-column AS column-aliaswhere
column-alias is a valid SAS name used as an aliaswhen referencing it in subsequent calculated column(s) in thecalculation, use the alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 12 / 20
SQL—An Introduction Introduction to PROC SQL
Using Column Alias
input-column AS column-aliaswhere
column-alias is a valid SAS name used as an aliaswhen referencing it in subsequent calculated column(s) in thecalculation, use the alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 12 / 20
SQL—An Introduction Introduction to PROC SQL
Using Column Alias
input-column AS column-aliaswhere
column-alias is a valid SAS name used as an aliaswhen referencing it in subsequent calculated column(s) in thecalculation, use the alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 12 / 20
SQL—An Introduction Introduction to PROC SQL
Adding Text to Output
Codesdata test;do r = rank(’A’) to rank(’Z’);c = byte(r);output;
end;run;proc sql;select ’Character’ format=$9.,
r label=’#’ format=2.,’is’, c ’#’
from test;quit;
Output--------------------Character 65 is ACharacter 66 is BCharacter 67 is CCharacter 68 is Dmore output lines here
Character 90 is Z
wang (WMU) SAS SQL #1 Lecture 19 13 / 20
SQL—An Introduction Introduction to PROC SQL
Adding Text to Output
Codesdata test;do r = rank(’A’) to rank(’Z’);c = byte(r);output;
end;run;proc sql;select ’Character’ format=$9.,
r label=’#’ format=2.,’is’, c ’#’
from test;quit;
Output--------------------Character 65 is ACharacter 66 is BCharacter 67 is CCharacter 68 is Dmore output lines here
Character 90 is Z
wang (WMU) SAS SQL #1 Lecture 19 13 / 20
SQL—An Introduction Introduction to PROC SQL
Adding Text to Output
Codesdata test;do r = rank(’A’) to rank(’Z’);c = byte(r);output;
end;run;proc sql;select ’Character’ format=$9.,
r label=’#’ format=2.,’is’, c ’#’
from test;quit;
Output--------------------Character 65 is ACharacter 66 is BCharacter 67 is CCharacter 68 is Dmore output lines here
Character 90 is Z
wang (WMU) SAS SQL #1 Lecture 19 13 / 20
SQL—An Introduction Introduction to PROC SQL
Calculated Column
created byarithmatic-expression <AS alias> <attributes>where alias is required if it is referenced in subsequentcalculated column(s)referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 14 / 20
SQL—An Introduction Introduction to PROC SQL
Calculated Column
created byarithmatic-expression <AS alias> <attributes>where alias is required if it is referenced in subsequentcalculated column(s)referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 14 / 20
SQL—An Introduction Introduction to PROC SQL
Calculated Column
created byarithmatic-expression <AS alias> <attributes>where alias is required if it is referenced in subsequentcalculated column(s)referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 14 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By CASE Expression
created byCASEWHEN cond-1 THEN expr-1more WHEN-THEN clauses as neededELSE expr-2
END <AS alias> <attributes>
referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 15 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By CASE Expression
created byCASEWHEN cond-1 THEN expr-1more WHEN-THEN clauses as neededELSE expr-2
END <AS alias> <attributes>
referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 15 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By CASE Expression
created byCASEWHEN cond-1 THEN expr-1more WHEN-THEN clauses as neededELSE expr-2
END <AS alias> <attributes>
referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 15 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By CASE-Operand Expression
created byCASE operandWHEN value-1 THEN expr-1more WHEN-THEN clauses as neededELSE expr-2
END <AS alias> <attributes>
referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 16 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By CASE-Operand Expression
created byCASE operandWHEN value-1 THEN expr-1more WHEN-THEN clauses as neededELSE expr-2
END <AS alias> <attributes>
referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 16 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By CASE-Operand Expression
created byCASE operandWHEN value-1 THEN expr-1more WHEN-THEN clauses as neededELSE expr-2
END <AS alias> <attributes>
referencing it byCALCULATED alias
See example sql01.sas.
wang (WMU) SAS SQL #1 Lecture 19 16 / 20
SQL—An Introduction Introduction to PROC SQL
Column Created By COALESCE FunctionUsage:COALESCE(col-1,col-2<, ...>)
<AS alias> <attributes>returns first non-missing value of the columns; returns missing value if allmissing. For example,
select Name,coalesce(LowPoint, ’*Not Available*’) as LowPoint
from mylib.continents;select Name,
casewhen LowPoint is missing then ’*Not Available*’else LowPoint
end as LowPointfrom mylib.continents;
wang (WMU) SAS SQL #1 Lecture 19 17 / 20
SQL—An Introduction Introduction to PROC SQL
Subset Input Table Using WHERE ClauseSELECT input-columns
FROM tableWHERE cond;
where cond is expression that makes use oftable columns and/or input columns and with comparisonoperators (symbols or mnemonics), logical operators (symbols ormnemonics)special operators including BETWEEN-AND, CONTAINS, IN, ISNULL/IS MISSING, LIKE, and =∗truncated string comparison operators (3-letter mnemonicsformed by appending 2-letter comparison operators)special operators linking subquery: ANY (subquery), ALL(subquery), and EXISTS (subquery)
wang (WMU) SAS SQL #1 Lecture 19 18 / 20
SQL—An Introduction Introduction to PROC SQL
Subset Input Table Using WHERE ClauseSELECT input-columns
FROM tableWHERE cond;
where cond is expression that makes use oftable columns and/or input columns and with comparisonoperators (symbols or mnemonics), logical operators (symbols ormnemonics)special operators including BETWEEN-AND, CONTAINS, IN, ISNULL/IS MISSING, LIKE, and =∗truncated string comparison operators (3-letter mnemonicsformed by appending 2-letter comparison operators)special operators linking subquery: ANY (subquery), ALL(subquery), and EXISTS (subquery)
wang (WMU) SAS SQL #1 Lecture 19 18 / 20
SQL—An Introduction Introduction to PROC SQL
Subset Input Table Using WHERE ClauseSELECT input-columns
FROM tableWHERE cond;
where cond is expression that makes use oftable columns and/or input columns and with comparisonoperators (symbols or mnemonics), logical operators (symbols ormnemonics)special operators including BETWEEN-AND, CONTAINS, IN, ISNULL/IS MISSING, LIKE, and =∗truncated string comparison operators (3-letter mnemonicsformed by appending 2-letter comparison operators)special operators linking subquery: ANY (subquery), ALL(subquery), and EXISTS (subquery)
wang (WMU) SAS SQL #1 Lecture 19 18 / 20
SQL—An Introduction Introduction to PROC SQL
Subset Input Table Using WHERE ClauseSELECT input-columns
FROM tableWHERE cond;
where cond is expression that makes use oftable columns and/or input columns and with comparisonoperators (symbols or mnemonics), logical operators (symbols ormnemonics)special operators including BETWEEN-AND, CONTAINS, IN, ISNULL/IS MISSING, LIKE, and =∗truncated string comparison operators (3-letter mnemonicsformed by appending 2-letter comparison operators)special operators linking subquery: ANY (subquery), ALL(subquery), and EXISTS (subquery)
wang (WMU) SAS SQL #1 Lecture 19 18 / 20
SQL—An Introduction Introduction to PROC SQL
Subset Input Table Using WHERE ClauseSELECT input-columns
FROM tableWHERE cond;
where cond is expression that makes use oftable columns and/or input columns and with comparisonoperators (symbols or mnemonics), logical operators (symbols ormnemonics)special operators including BETWEEN-AND, CONTAINS, IN, ISNULL/IS MISSING, LIKE, and =∗truncated string comparison operators (3-letter mnemonicsformed by appending 2-letter comparison operators)special operators linking subquery: ANY (subquery), ALL(subquery), and EXISTS (subquery)
wang (WMU) SAS SQL #1 Lecture 19 18 / 20
SQL—An Introduction Introduction to PROC SQL
Summarizing Datausing aggregate functions
Aggregate functions (or summary functions) are used to combinecolumns. If single column is specified then the column statistic isproduced; otherwise, row statistics are produced for the columns.Aggregate functions include
1 AVG/MEAN, MIN, MAX, SUM SUMWGT2 RANGE, STD, STDERR, CV3 USS, CSS, VAR4 COUNT, FREQ, N, NMISS5 T, PRT
wang (WMU) SAS SQL #1 Lecture 19 19 / 20
SQL—An Introduction Introduction to PROC SQL
Summarizing Datausing aggregate functions
Aggregate functions (or summary functions) are used to combinecolumns. If single column is specified then the column statistic isproduced; otherwise, row statistics are produced for the columns.Aggregate functions include
1 AVG/MEAN, MIN, MAX, SUM SUMWGT2 RANGE, STD, STDERR, CV3 USS, CSS, VAR4 COUNT, FREQ, N, NMISS5 T, PRT
wang (WMU) SAS SQL #1 Lecture 19 19 / 20
SQL—An Introduction Introduction to PROC SQL
Sorting Query Results
SELECT input-columnFROM tableORDER BY sort-columns;
where columns is a comma-separated list of columns and eachsort-column
can be an input-column either by name or by its position (anumber) in the input-column listcan be a table column but not an input columnif it’s a calculated column, do NOT use CALCULATED keyworduse sort-column DESC for a sort-column to be in descendingorder
wang (WMU) SAS SQL #1 Lecture 19 20 / 20
SQL—An Introduction Introduction to PROC SQL
Sorting Query Results
SELECT input-columnFROM tableORDER BY sort-columns;
where columns is a comma-separated list of columns and eachsort-column
can be an input-column either by name or by its position (anumber) in the input-column listcan be a table column but not an input columnif it’s a calculated column, do NOT use CALCULATED keyworduse sort-column DESC for a sort-column to be in descendingorder
wang (WMU) SAS SQL #1 Lecture 19 20 / 20
SQL—An Introduction Introduction to PROC SQL
Sorting Query Results
SELECT input-columnFROM tableORDER BY sort-columns;
where columns is a comma-separated list of columns and eachsort-column
can be an input-column either by name or by its position (anumber) in the input-column listcan be a table column but not an input columnif it’s a calculated column, do NOT use CALCULATED keyworduse sort-column DESC for a sort-column to be in descendingorder
wang (WMU) SAS SQL #1 Lecture 19 20 / 20
SQL—An Introduction Introduction to PROC SQL
Sorting Query Results
SELECT input-columnFROM tableORDER BY sort-columns;
where columns is a comma-separated list of columns and eachsort-column
can be an input-column either by name or by its position (anumber) in the input-column listcan be a table column but not an input columnif it’s a calculated column, do NOT use CALCULATED keyworduse sort-column DESC for a sort-column to be in descendingorder
wang (WMU) SAS SQL #1 Lecture 19 20 / 20
SQL—An Introduction Introduction to PROC SQL
Sorting Query Results
SELECT input-columnFROM tableORDER BY sort-columns;
where columns is a comma-separated list of columns and eachsort-column
can be an input-column either by name or by its position (anumber) in the input-column listcan be a table column but not an input columnif it’s a calculated column, do NOT use CALCULATED keyworduse sort-column DESC for a sort-column to be in descendingorder
wang (WMU) SAS SQL #1 Lecture 19 20 / 20
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