The DESCRIBE Statement in Software

Paint Code-128 in Software The DESCRIBE Statement

The DESCRIBE Statement
Code 128 Recognizer In None
Using Barcode Control SDK for Software Control to generate, create, read, scan barcode image in Software applications.
Encode USS Code 128 In None
Using Barcode printer for Software Control to generate, create Code 128B image in Software applications.
The Oracle DESCRIBE statement is used, like the DB2 DESCRIBE statement, to describe the query results of a dynamic query. Like DB2, Oracle returns the descriptions in a SQLDA. The Oracle DESCRIBE statement can also be used to request a description of
Scanning Code 128B In None
Using Barcode scanner for Software Control to read, scan read, scan image in Software applications.
Encoding Code 128C In C#.NET
Using Barcode creator for .NET framework Control to generate, create Code 128 Code Set A image in .NET applications.
18:
Encode USS Code 128 In .NET
Using Barcode generator for ASP.NET Control to generate, create Code 128B image in ASP.NET applications.
Print USS Code 128 In VS .NET
Using Barcode maker for .NET Control to generate, create Code 128 Code Set B image in .NET applications.
Dynamic SQL *
Code 128 Code Set A Printer In Visual Basic .NET
Using Barcode generator for VS .NET Control to generate, create Code 128 Code Set B image in VS .NET applications.
Code-39 Generator In None
Using Barcode maker for Software Control to generate, create USS Code 39 image in Software applications.
the named parameters in a dynamically prepared statement. Oracle also returns these parameter descriptions in a SQLDA. This Oracle DESCRIBE statement requests a description of the columns of query results from a previously prepared dynamic query:
Data Matrix 2d Barcode Creator In None
Using Barcode creator for Software Control to generate, create Data Matrix 2d barcode image in Software applications.
Drawing Code128 In None
Using Barcode drawer for Software Control to generate, create Code 128 image in Software applications.
exec sql describe select list for qrystmt into qry_sqlda;
Bar Code Creator In None
Using Barcode generation for Software Control to generate, create bar code image in Software applications.
UPC A Encoder In None
Using Barcode creation for Software Control to generate, create UPCA image in Software applications.
It corresponds to the DB2 statement:
Leitcode Creator In None
Using Barcode printer for Software Control to generate, create Leitcode image in Software applications.
ean 13 barcode excel vba
Using Barcode creator for Microsoft Excel Control to generate, create GS1 - 13 image in Office Excel applications. how to make barcodes in excel ean 13 barcode excel vba
exec sql describe qrystmt into qry_sqlda;
Making 1D In Java
Using Barcode creation for Java Control to generate, create Linear image in Java applications.
Decode USS Code 128 In Visual Studio .NET
Using Barcode reader for .NET framework Control to read, scan read, scan image in .NET framework applications.
This Oracle DESCRIBE statement requests a description of the named parameters in a previously prepared dynamic statement. The statement might be a query or some other SQL statement:
UPC-A Decoder In None
Using Barcode recognizer for Software Control to read, scan read, scan image in Software applications.
Painting EAN 128 In .NET
Using Barcode generator for ASP.NET Control to generate, create UCC.EAN - 128 image in ASP.NET applications.
exec sql describe bind list for thestmt into the_sqlda;
Barcode Creator In None
Using Barcode creation for Font Control to generate, create bar code image in Font applications.
Generating Code-128 In Java
Using Barcode encoder for Android Control to generate, create Code 128 image in Android applications.
This Oracle statement has no DB2 equivalent. Following this DESCRIBE statement, your program would typically examine the information in the SQLDA, fill in the pointers in the SQLDA to point to the parameter values the program wants to supply, and then execute the statement using the SQLDA form of the OPEN or EXECUTE statement:
exec sql execute thestmt using descriptor the_sqlda; exec sql open qrycursor using descriptor the_sqlda;
The information returned by both forms of the Oracle DESCRIBE statement is the same, and is described in the next section.
The Oracle SQLDA
The Oracle SQLDA performs the same functions as the DB2 SQLDA, but its format, shown in Figure 18-16, differs substantially from that of DB2. The two important fields in the DB2 SQLDA header both have counterparts in the Oracle SQLDA: I The N field in the Oracle SQLDA specifies the size of the arrays used to hold column definitions. It corresponds to the SQLN field in the DB2 SQLDA. I The F field in the Oracle SQLDA indicates how many columns are currently described in the arrays of the SQLDA. It corresponds to the SQLD field in the DB2 SQLDA.
PROGRAMMING WITH SQL
SQL: The Complete Reference
struct sqlda { int N; /* number of entries in the SQLDA arrays */ char **V; /* pointer to array of pointers to data areas */ int *L; /* pointer to array of buffer lengths */ short *T; /* pointer to array of data type codes */ short **I; /* pointer to array of pointers to indicator variables */ int F; /* number of active entries in the SQLDA arrays */ char **S; /* pointer to array of pointers to column/parameter names */ short *M; /* pointer to array of name buffer lengths */ short *C; /* pointer to array of current lengths of names */ char **X; /* pointer to array of pointers to indicator parameter names */ short *Y; /* pointer to array of indicator name buffer lengths */ short *Z; /* pointer to array of current lengths of indicator names */ } ;
Figure 18-16.
The Oracle SQLDA
Instead of DB2 s single array of SQLVAR structures that contain column descriptions, the Oracle SQLDA contains pointers to a series of arrays, each of which describes one aspect of a column: I The T field points to an array of integers that specify the data type for each query results column or named parameter. The integers in this array correspond to the SQLTYPE field in each DB2 SQLVAR structure. I The V field points to an array of pointers that specify the buffer for each column of query results or each passed parameter value. The pointers in this array correspond to the SQLDATA field in each DB2 SQLVAR structure. I The L field points to an array of integers that specify the length of each buffer pointed to by the V array. The integers in this array correspond to the SQLLEN field in each DB2 SQLVAR structure. I The I field points to an array of data pointers that specify the indicator variable for each query results column or named parameter. The pointers in this array correspond to the SQLIND field in each DB2 SQLVAR structure. I The S field points to an array of string pointers that specify the buffers where Oracle is to return the name of each query results column or named parameter. The buffers pointed to by this array correspond to the SQLNAME structure in each DB2 SQLVAR structure.
18:
Dynamic SQL *
I The M field points to an array of integers that specify the size of each buffer pointed to by the S array. For DB2, the SQLNAME structure has a fixed-length buffer, so there is no equivalent to the M field. I The C field points to an array of integers that specify the actual lengths of the names pointed to by the S array. When Oracle returns the column or parameter names, it sets the integers in this array to indicate their actual lengths. For DB2, the SQLNAME structure has a fixed-length buffer, so there is no equivalent to the C field. I The X field points to an array of string pointers that specify the buffers where Oracle is to return the name of each named indicator parameter. These buffers are used only by the Oracle DESCRIBE BLIND LIST statement; they have no DB2 equivalent. I The Y field points to an array of integers specifying the size of each buffer pointed to by the X array. There is no DB2 equivalent. I The Z field points to an array of integers specifying actual lengths of the indicator parameter names pointed to by the X array. When Oracle returns the indicator parameter names, it sets the integers in this array to indicate their actual lengths. There is no DB2 equivalent.
Copyright © OnBarcode.com . All rights reserved.